Day 1 - SLU COMPI Flashcards by Mark Andrew Sion

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Which of the following would you expect to form the strongest bonds to carbon? A. Li B. Na C. K D. Rb

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Consider the following reaction at 1600˚C: Br2(g) ↔ 2Br(g).

When 1.05 moles of Br2 are placed in a 2L flask, 2.5% of Br2undergoes dissociation. Calculate the Kp for the reaction. A. 0.20869 B. 0.001346 C. 3.7216 D. 0.0953

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What will be the likely combination of ionization energy and electron affinity for an element that has a very low electronegativity? A. High ionization energy, high electron affinity B. High ionization energy, low electron affinity C. Low ionization energy, high electron affinity D. Low ionization energy, low electron affinity

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Consider the reaction: PCl5(g) ↔ PCl3(g)+ Cl2(g)

ΔHrxn = 87.9 kJ/mol

Which of the following will result in the increase in concentration of Cl2 gas? a. Add PCl 3 B. Cool the mixture C. add PCl 5 D. increase the pressure

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The average atomic mass of Ga is 69.72. Naturally occurring Ga is composed of 60.0% 69Ga, which has an atomix mass of 68.91, and 40.0% 71Ga. What is the atomic mass of 71Ga? a. 69.72 amu b. 69.92 amu c. 70.94 amu d. 71.00 amu

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All of the following are chemical processes except
a. Liquid vaporizing to form a gas b. The conversion of starch to carbon dioxide and water in an animal c. An acid dissolving a metal d. Rusting of iron

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In what group of the periodic table is the element with the following electron configuration? [Ar] 4s2 3d10 4p3 a. 1A b. 2A c. 3A d. 5A

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The vapor pressure of water at 25˚C is 23.756 torr. A solution consisting of 18.913 grams of a non-volatile substance in 36 grams of water has a vapor pressure of 20.234 torr. What is the molecular weight of the solute? a. 62 b. 54 c. 48 d. 39

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The atomic weight of chlorine is 35.45 and its naturally occurring isotopes are Cl-35 and Cl-37. What is the percentage abundance of Cl-35? a. 95.8% b. 98.7% c. 77.5% d. 75.0%

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Starting with 1.0 gram of Sr-90, 0.953 grams will remain after 2 years. Calculate the initial activity of Sr-90 in Ci. 1 Curie(Ci)= 3.70 x 10^10 disintegration/sec a. 70 b. 140 c. 210 d. 280

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Starting with 2-methyl-2-butene, which of the following processes must be used to produce a secondary alcohol? a. Acid-catalyzed hydration b. Oxymercuration-demercuration c. Addition of bromine water d. Hydroboration-oxidation

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The Lewis structure of SF2 has ___ lone pairs of electrons and ___ double bonds. a. 8,0 b. 6,0 c. 4,1 d. 2,2

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When a straight chain alkene undergoes sulfuric acid catalyzed hydration, the primary product is a a. primary alcohol b. secondary alcohol c. tertiary alcohol d. quaternary alcohol

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How many isomers are there of the chlorinated alkane with the formula C3H6Cl2? a. 2 b. 3 c. 4 d. 5

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Lead (Pb) crystallizes in a face-centered cubic lattice with a unit cell edge of 4.941. What is the density of lead? (l = 10^-8 cm) a. 2.78 x 10-14 g/cm3 b. 2.85 g/cm3 c. 5.70 g/cm3 d. 11.4 g/cm3

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The energy sublevel that can contain the most electrons is specified by which of the following quantum number descriptions? a. n=2, l=1 b. n=3, l=2 c. n=4, l=3 d. n=5, l=0

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To answer the following question, you will need to recall for the 14C isotope found in living matter t = 5720 years and the decay rate is 15 decays/g.min. If 20 grams of charcoal scrapings from the wall of a prehistoric cave dwelling are decaying at a rate of 2.0 disintegrations/minute then the writings must be a. 500 yrs old b. 5720 yrs old c. 11000 yrs old d. 22000 yrs old

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How many monochlorinated product is expected from the chlorination of propane? a. 1 b. 2 c. 3 d. 4

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A compound containing only C and H gives 0.518 g of H2O and 2.13 g of CO2 when fully combusted in oxygen. What is its simplest or empirical formula? a. CH9 b. C5H3 c. C5H6 d. C3H4

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Hydrolysis of an ester leads to two compounds. Which of the following pairs compounds is formed from such a hydrolysis? a. an alcohol and an aldehyde b. two alcohols
c. an alcohol and a carboxylic acid
d. a ketone and a carboxylic acid

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What is the molarity of a KMnO4 solution standardized against 1.356 gram Na2C2O4 requiring 25.1 mL of the solution in acidic medium?
a. 0.161 M b. 0.403 M c. 1.008 M d. 0.856 M

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The 300 mg sample of impure Na2SO4 (MW= 142.04) was dissolved in sufficient water and the sulfate was precipitated by the addition of 35.00 mL of 0.1022 M BaCl2. The precipitate was removed by filtration and the remaining BaCl2 consumed 6.79 mL of 0.2467 M EDTA for titration to the Calgamite endpoint. Calculate the purity of the sample.
A. 80% B. 85% C. 90% D. 95%

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25 mL of a monoprotic unknown acid is titrated to an end point with 0.10 M NaOH at 32.2 mL. At the point where 16.1 mL of base has been added, the pH of the solution is 5.5. What is the value of Ka for the unknown acid?
A. 1.6x10-6 B. 3.2x10-6 C. 6.4x10-6 D. 1.3x10-5

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A closed vessel contains an inert gas at 500 torr and 60degC. What is the total pressure (in torr) inside the vessel after a few drops of liquid B are injected and equilibrium is established at 60degC with B present as both liquid and vapor? The vapor pressure of liquid B at 60degC is 80 torr. a. 420 torr b. 500 torr c. 560 torr d. 580 torr

An EDTA solution was prepared by dissolving the disodium salt in 1L of water. It was standardized using 0.5063 gram of primary standard CaCO3 and consumed 28.50 mL of the solution. The standard solution was used to determine the hardness of a 2L sample of mineral water, which required 35.57 mL of the EDTA solution. Express the analysis in terms of ppm CaCO3. a. 89 ppm b. 316 ppm c. 158 ppm d. 269 ppm

A sample pyrolusite weighing 0.24 gram was treated with excess KI. The iodine liberated required 46.24 mL of 0.1105M Na2S2O3 solution. Calculate the %MnO2 (86.94 g/mol) in the sample. a. 46.27% b. 30.85% c. 92.54% d. 76.12%

A 100 mL water sample was analyzed by Winkler Method. If 7.52mL of 0.0124 M Na2S2O3 was used for titration, determine the ppm of O2 in the water sample. a. 2.8 b. 3.5 c. 6.4 d. 7.5

If 4.27 g of sucrose, C12H22O11 are dissolved in 15.2 g of water, what will be the boiling point of the resulting solution? (Kb for water = 0.512 K/m. The normal boiling point of water is 100degC) a. 101.64 degC b. 100.42 degC c. 99.62 degC d. 100.73 degC

A 1.5 gram sample of impure aluminum chloride was dissolved in water and treated with 45.32 mL of 0.1000 M AgNo3 using K2CrO4 as indicator. Express the analysis in %AlCl3 (MW= 133.33). a. 40.28% b. 13.43% c. 4.48% d. 27.36%

A 10.0 gram sample of cooked-ham was pureed with 200 mL of water, filtered and the resulting solution containing dissolved potassium nitrite was acidified. This solution was treated with 25.0 mL of 0.00514 M KMnO4 and was back titrated with 14.97 mL of 0.01678 M FeSO4. Calculate the amount of nitrite (46.01 g/mol) in ppm. a. 450 b. 900 c. 1350 d. 1800

Silver crystallizes with a face-centered cubic unit cell. The radius of a silver atom is 0.144 nm. Calculate the density of solid silver. Ag= 107.87 g/mol a. 24.8 g/ml b. 21.2 g/ml c. 15.7 g/ml d. 10.6 g/ml

The law relating the solubility of the gas to its pressure is called a. Raoult's Law b. Distribution Law c. Henry's Law d. Arrhenius Law

How many moles of sugar must be added to 100 g to lower the freezing point of the solution by 1degC? The value of Kf for water is -1.86 K/m. a. 0.5 b. 0.27 c. 0.054 d. 0.027

Absolute zero may be regarded as that temperature at which a. all gases become liquids b. molecular motion ceases c. all substances are solids d. water freezes

In the equation for the reaction of potassium iodide (KI) and sulfuric acid (H2SO4), which statement is true? 8KI(aq) + 9H2SO4(aq) → 4I2 (s) + 8KHSO4(aq) + H2S(g) + 4H2O(l) a. The reducing agent is H2SO4 b. The oxidizing agent is KI c. The substance reduced is H2SO4 d. The substance oxidized is KHSO4

Ethanol is to be used in an automobile carburetor that is adjusted to give a 9:1 air -fuel ratio (mass ratio). If the temperature in the manifold is 60 ˚F and the pressure is atmospheric. What percentage of the alcohol will be evaporated assuming that equilibrium between vapor and liquid is reached? Vapor pressure of ethanol at 60 ˚F is 33.75 mmHg. a. 56% b. 76% c. 66% d. 90%

The correct ordering of the relative solubility of AgCl(s) in water and aqueous solutions of 0.1 M silver nitrate and 0.1 M ammonia is: (1) in pure water, (2) in 0.1M AgNO3, (c) in 0.1 M aq NH3 a. 1>3>2 b. 2>3>1 c. 3>1>2 d. 3>2>1

Fe crystallizes in a body-centered cubic lattice. The density of iron is 7.86 g/cm3. Calculate the atomic radius of iron in angstrom. a. 1.24 b. 2.48 c. 0.62 d. 0.62

A solution of 0.72% wt HCl, freezes at -0.706 ˚C. Calculate the apparent molecular weight of HCl. a. 38.2 b. 37.8 c. 37.1 d. 36.5

What moves between the two half-cells of a galvanic cell? a. electrons only b. ions only c. ions and electrons d. the cells are separated from each other so that there will be no transfer between them

Which of the following is an example of a thermoset polymer? a. formica b. polyethylene c. polystyrene d. poly(vinyl)chloride

In which of the following molecules (all linear and linked together as written) is the carbon an sp2 hybrid? a. FCCF b. OCCO c. NCCN d. none of the choices

Which of the following is a detergent? a. fatty alcohol b. alkyl benzene sulfonate c. fatty acids d. methyl chloride

Type of wastewater treatment that employs biological methods to remove fine suspended, colloidal and dissolved organics by biochemical oxidation. a. primary treatment b. secondary treatment c. tertiary treatment d. minor treatment

The process of fermentation can be considered to be a. oxidation b. dehydration c. anaerobic respiration d. aerobic respiration

Process of converting nitrogen gas to ammonia is called a. ammonification b. denitrification c. nitrogen fixation d. ammonolysis

Nutrient for cellular growth is called a. protein b. substrate c. carbohydrate d. lipid

The reduction of carbon dioxide with magnesium powder and turnings releases energy and is therefore (exothermic, endothermic) and the expanding of carbon dioxide from an extinguisher is (isothermal, adiabatic). a. exothermic, isothermal b. exothermic, adiabatic c. endothermic, isothermal d. endothermic, adiabatic

A water solution of molasses contains 10% by weight sucrose (C12H22O11). The CO2 formed in the reaction can be considered having negligible solubility in the solution and the last 10% of the sugar can be assumed unchanged. The weight percent of ethyl alcohol in the solution after 90% of the sucrose has been converted to ethyl alcohol by fermentation is a. 6.5% b. 5.6% c. 5.1% d. 6%

It is desired to reduce the bacterial count of polluted water from 8 million organisms per mL to 17 organisms per mL. The number of completely mixed chlorine contact chambers in series, each having a detention time of 40 minutes, that would be required if the first order removal rate constant is 8 per hour is a. 5 vessels b. 7 vessels c. 10 vessels d. 8 vessels

When 1.827 g of a hydrocarbon, CxHy, was burned in a combustion analysis apparatus, 6.373g of CO2 and 0.7829 g of H2O were produced. In a separated experiment the molar mass of the compound was found to be 252.31 g/mo. Determine the empirical formula and molecular formula of the hydrocarbon. a. EF: C4H2; MF: C23H15 b. EF: C6H7; MF: C15H8 c. EF: C7H4; MF: C17H10 d. EF: C5H3; MF: C20H12

Which of the following units of concentration will change in value for a particular solution if the temperature changes? a. mole fraction b. molarity c. molality d. none will change

One way to reduce air pollution is to remove potential pollutant gases from an exhaust stream before they are released into the air. Carbon dioxide can be removed from a stream of gas by reacting it with calcium oxide to form calcium carbonate. If we react 5.50 L of CO2 at STP with excess CaO, what mass of calcium carbonate will form? a. 12.5 g b. 34.8 g c. 45 g d. 24.6 g

Suppose that you have a part that requires a tin coating. You’ve calculated that you need to deposit 3.60 g of tin to achieve an adequate coating. If your electrolysis cell (using Sn2+) runs at 2.00 A, how long must you operate the cell to obtain the desired coating? a. 48.8 mins b. 50.5 mins c. 37.2 mins d. 68.3 mins

A piece of cloth is discovered in a burial pit in the southwestern United States. A tiny sample of the cloth is burned to CO2, and the 14C/12C ratio is 0.250 times the ratio in today’s atmosphere. How old is the cloth? a. 11500 yrs b. 15000 yrs c. 24800 yrs d. 28300 yrs

Which of the following statements is true? a. Oxidations always have positive potential and reductions have negative potentials. b. Half-reactions that have negative half-cell potentials cannot be part of a galvanic (spontaneous) cell under standard conditions. c. An unreactive metal like gold is very difficult. Therefore, it is very difficult to reduce gold ions to gold metal. d. Assigning a potential of 0 V to the hydrogen ion/hydrogen gas electrode is purely arbitrary and it could have been assigned any other value.

In a laboratory experiment, 2.175 g of lysine, an amino acid containing C, H, O, N, underwent combustion to produce 3.94 g of CO2 and 1.89 g H2O. In another experiment, 1.873 g of lysine was burned and formed 0.436 g of NH3. The molar mass of lysine is 150 g/mol. Determine empirical and molecular formula of lysine a. EF: C2H2O ; MF: C6H14N2O2 b. EF: CH2N2O ; MF: C7H12N2O c. EF: C3H2NO ; MF: C6H14N2O2 d. EF: C4H3N2O ; MF: C8H16NO2

All of the following are true concerning the calculation of the formula of a compound from the percentage composition of its elements only EXCEPT a.It is assumed that the atoms of the elements are combined in ratios of reasonably small whole number. b. The calculation can be based on the idea of starting with 100 g of compound. c. The actual molecular formula can be calculated. d. The relative ratios of the numbers of the different atoms in the compound can be determined.

The reduction of carbon dioxide to carbon monoxide would best be successfully carried out by reaction with a. carbon b. oxygen c. carbon and oxygen d. magnesium

All of the following are assumptions made in the Bohr theory EXCEPT a. The forces of circular motion and coulombic attraction exactly balance. b. The electron in its orbit neither absorbs or emits energy. c. The electron can occupy only certain orbits d. The nucleus consists of protons and neutrons

A chemist requires 1.5 M hydrochloric acid, HCl, for a series of reactions. The only solution available is 6.0 M HCl. What volume of 6.0 M HCl must be diluted to obtain 5.0 L of 1.5 M HCl? a. 0.76 L b. 2 L c. 1.3 L d. 3.2 L

Which of the following cannot be determined from the molecular formula of the compound C5H12? a. the molecular mass b. the mass percent of the compound that is C c. the mass percent of the compound that is H d. density of compound

Assume that you have a cell that has an iron(II) concentration of 0.015 M and an H1 concentration of 1.0 3 1023 M. The cell temperature is 38°C, and the pressure of hydrogen gas is maintained at 0.04 atm. What would the cell potential be under these conditions? a. 0.56 V b. 0.35 V c. 0.45 V d. 0.67 V

What is the standard cell potential for the following galvanic cell? Cu(s) | Cu2+ (1M) || Ag+ (1M) | Ag(s) a. 0.357 V b. 0.143 V c. 0.462 V d. 0.280 V

Which of the following is not a form of electromagnetic radiation? a. light b. radiated heat c. sound d. microwaves

Suppose that we wish to study the possible galvanic corrosion between zinc and chromium, so we set up the following cell: Cr(s) | Cr2+ (aq) || Zn2+(aq) | Zn(s) What is the chemical reaction that takes place, and what is the standard free energy change for that reaction? a. -28.4 kJ b. -15.7 kJ c. -32.5 kJ d. -45.6 kJ

Which of the following is one of the principal gases that is responsible for acid rain? a. CH4 b. SF6 c. Cl2 d. SO2

An electrolysis cell that deposits gold (from Au1(aq)) operates for 15.0 minutes at a current of 2.30 A. What mass of gold is deposited? a. 3.33 g b. 4.23 g c. 5.67 g d. 2.39 g

The Solvay process is important in the commercial production of sodium carbonate (Na2CO3), which is used in the manufacture of most glass. The last step in the Solvay process is the conversion of NaHCO3 (sodium bicarbonate, or baking soda) to Na2CO3 by heating. 2 NaHCO3(s) → Na2CO3(s) + CO2(g) + H2O(g) In a laboratory experiment, a student heats 42.0 g of NaHCO3 and determines that 22.3 g of Na2CO3 is formed. What is the percentage yield of this reaction? a. 84.2% b. 75.7% c. 67.0% d, 53.2%

The equilibrium constant for the reaction of chlorine gas with phosphorus trichloride to form phosphorus pentachloride is 33 at 250°C. If an experiment is initiated with concentrations of 0.050 M PCl3 and 0.015 M Cl2, what are the equilibrium concentration of all three gases? Cl2(g) + PCl3(g) ↔ PCl5(g) a. [PCl5] = 0.0054 M ; [Cl2] = 0.006 M ; [PCl3] = 0.067 M b. [PCl5] = 0.0075 M ; [Cl2] = 0.004 M ; [PCl3] = 0.052 M c. [PCl5] = 0.0088M ; [Cl2] = 0.006 M ; [PCl3] = 0.041 M d. [PCl5] = 0.0063 M ; [Cl2] = 0.007 M ; [PCl3[ = 0.042 M

Not all pollution is due to human activity. Natural sources, including volcanoes, also contribute to air pollution. A scientist tries to generate a mixture of gases similar to those found in a volcano by introducing 15.0 g of water vapor, 3.5 g of SO2 and 1.0 g of CO2 into a 40.0-L vessel held at 120.0°C. Calculate the partial pressure of each gas and the total pressure. a. P total = 0.543 atm b. P total = 0.734 atm c. P total = 0.856 atm d. P total = 0.623 atm

When hydrogen gas reacts with iodine gas at elevated temperatures, the following equilibrium is established: H2(g) + I2(g) ↔ 2 HI(g) A student measured the equilibrium constant as 59.3 at 400°C. If one trial begins with a mixture that includes 0.050 M hydrogen and 0.050 M iodine, what will be the equilibrium concentrations of reactants and products? a. [H2] = 0.03 M ; [I2] = 0.03 M ; [HI] = 0.16 M b. {H2] = 0.01 M ; [I2] = 0.01 M ; [HI] = 0.16 M c. [H2] = 0.01 M ; [I2] = 0.01 M ; [HI] = 0.08 M d. [H2] = 0.03 M ; [I2] = 0.03 M ; [HI] = 0.08 M

The explosive known as RDX contains 16.22% carbon, 2.72% hydrogen, 37.84% nitrogen, and 43.22% oxygen by mass. What is the empirical formula of the compound? a. C2HNO2 b. CH2NO2 c. CH2N2O2 d. C2H2N2O

All of the following are true about a balanced equation except a. It always tells the exact manner in which elements and compounds in the equation will react. b. It is necessary for doing stoichiometric calculations. c. It can be used for determining chemical equivalences. d. It is a useful method for describing the nature of a chemical reaction.

The half-life of carbon-14, used in radiocarbon dating, is 5730 years. What is the decay constant for carbon-14? a. 11.21 x 104 /yr b. 15.32 x 104 /yr c. 8.57 x 104 /yr d. 19.63 x104 /yr

Which of the following atoms has the largest number of unpaired spins? a. C b. K c. P d. F

Aqueous solutions of sodium hypochlorite (NaClO) can be used in the synthesis of hydrazine (N2H4). Hydrazine has often been used as a rocket fuel, and a derivative of hydrazine is used as a fuel for engines in the orbital maneuvering system of the space shuttle. A solution is prepared by dissolving 45.0 g of NaClO in enough water to produce exactly 750 mL of solution. What is the molarity of the solution? a. 0.784 M b. 0.806 M c. 0.657 M d. 0.925 M

The active electrophile in the nitration of aromatic ring a. NO2- b. NO- c. NO2+ d. HNO2+

The Sandmeyer reaction is used to prepare a. phenols b. halo compounds c. diazo compounds d. nitro compounds

During hydrogenation of oils which of the following catalyst is commonly used. a. Ni b. Pd c. Fe d. V2O5

Addition of an alcohol to acyl halides produces a. carboxylic acid b. ester c. carboxamide d. none of these choices

When ammonium cyanate is heated, we get a. ammonium carbonate b. carbon monoxide c. urea d. carbon dioxide

Formalin is an aqueous solution of a. formic acid b. furfuraldehyde c. formaldehyde d. fluorescin

Which of the following are constitutional isomers of trans-1,2-dimethylcyclopentane? a. I, III, IV b. II, IV, V c. II, III, V d. III, IV, V

Which of the following carbocations has the highest energy? a. b. c. d.

Boiling point of acetone is a. 69 degC b. 75 degC c. 56 degC d. 90 degC

The normal electronic configuration of a molecule is known as its __________. a. ground state b. excited state c. valence electron d. wavelength

The number of xylene isomers is a. 1 b. 2 c. 3 d. NOTA

Which one of the following compounds does not react with bromine? a. ethylamine b. phenol c. chloroform d. propene

Lindlar’s catalyst is used to make _____________. a. cis-alkenes from alkynes b.trans-alkenes from alkynes c.alcohol from alkynes d. alkanes from alkynes

A liquid hydrocarbon is converted into a mixture of gaseous hydrocarbons by a. cracking b. oxidation c. hydrolysis d. ammonification

Homolytic formation of two reactive species with unpaired electrons. a. initiation b. propagation c. termination d. AOTA

Which statement does not describe a transition state? a. Possesses a definite geometry b. Maximum on the potential energy diagram c. Structure can be determined experimentally d. can not be isolated

An enzyme that catalyzes the dehydration of malate in the citric acid cycle. a. enolase b. fumarase c. lewisite d. nota

Which of the following properties are not identical for constitutional isomers? I. molecular formula II. molecular weight III. order of attachment of atoms IV. physical properties a. I, IV b. II, III c. I, II d. III, IV

The ∆G for conversion of ‘axial’ fluorocyclohexane to ‘equatorial’ fluorocyclohexane at 25degC is -0.25 kcal/mol. Calculate the percentage of fluorocyclohexane molecules that have the fluoro substituent in the equatorial position. a. 45% b. 60% c. 75% d. 80%`

Increasing the polarity of the solvent will _______ the rate of the reaction if none of the reactants in the rate-determining step is charged. a. increase b. double c. decrease d. constant

Sulfur tetrafluoride has _______ molecular geometry. a. linear b. see-saw c. T-shaped d. Trigonal

Rectified spirit contains a. 100% b. 75% c. 95.6% d. 85.7%

Which compounds contain stereocenters? I) 1-chloropentane II) 2-chloropentane III) 3-chloropentane IV) 1,2-dichloropentane a. I, II b. III, IV c. I, III d. II, IV

The combination of t-butyl carbonium ion with hydroxyl anion takes place by which of the following mechanism? a. SE2 b. SN1 c. SE1 d. SN2

An electron-poor specie a. cation b. electrophile c. anion d. nucleophile

The rate law for the substitution reaction of 2-bromobutane and HO- in 75% ethanol and 25% water at 30degC is Rate = (3.2x10^-5)[2-bromobutane][HO-] + (1.5x10^-6)[2-bromobutane]..What percentage of the reaction takes place by the SN2 mechanism when [HO-] = 1.00M a. 77% b. 48% c. 96% d. 69%

A dipole moment is a reported in a unit called a. amu b. debye c. esu d. degree A

Which of the following salts is expected to have the lowest solubility in water? a. NaF b. NaCl c. NaBr d. NaI

Which one of the following compounds does not react with bromine? a. ethylamine b. phenol c. chloroform d. propene

The negative part of the addendum adds on the carbon atom joined to the least number of hydrogen atoms. The statement is called a. peroxide effect b. baeyer's strain theory c. thiele's rule d. markovnikoff's rule

H+ means a. hydride b. hydrogen radical c. hydrogen ion d. all of he above

The highest energy point in a reaction step a. triple point b. logarithmic phase c. transition state d. NOTA

A species containing a positively charged carbon atom. a. radical b. carbanion c. carbocation d. cation

Increasing the polarity of the solvent will _______ the rate of the reaction if one or more reactants in the rate-determining step are charged. a. increase b. double c. decrease d. fourth

The phenomenon in which a steel needle can, with proper care, be made to float on the surface of some water illustrates a property of liquid known as: a. capillarity b. polarizability c. resistivity d. viscosity

If a large quantity of cobalt metal were dropped into a solution containing Ag+, Fe+2, Cu+2, the products of the reaction will be: a. Ag, Fe and Cu b. Ag, Fe++ and Cu+ c. Fe++, Cu and Co++ d. Fe++, Cu, Ag and Co++

A current of 9.65 ampere is drawn from a Daniel cell for exactly 1 hour. The loss of mass of anode is a. 0.180 g b. 23.6 g c. 0.197 g d. 11.8 g

An ideal gas differs from a real gas in that the molecules of an ideal gas _________________. a. have no attraction for one another b. have appreciable molecular volume c. Have a molecular weight of zero d. have no kinetic energy e. has an average molecular mass

The fact that a balloon filled with helium will leak more slowly than one filled with hydrogen is explained by citing: a. avogadro's hypothesis b. dalton's law c. graham's law d. van der waals theory

If someone were to light a cigar at one end of a closed room, persons at the other end of the room might soon perceive an odor due to gaseous emissions from the cigar. Such a phenomenon is an example of: a. monometry b. ideality c. effusion d. diffusion

Of the following, ____________ is characteristic of gases. a. Gases are highly compressible. b. These are relatively large distances between molecules c. Gases form homogenous mixtures regardless of the non-reacting gas components d. All of these.

The first person to investigate the relationship between the pressure of a gas ad its volume was a. Amadeo Avogadro b. Lord Kelvin c. Jacques Charles d. Robert Boyle

When a liquid is in equilibrium with its vapor in a closed container: a. The rate at which molecules from the liquid phase enter the gas phase exactly equals the rate at which molecules from the gas phase pass into the liquid phase b. A change in temperature will not change the pressure in the container c. The amount of gas in the container must exactly equal the amount of liquid d. Molecules cannot go from the liquid phase to the gas phase because the amount of liquid in the container is constant

The following reaction does not occur spontaneously (all ions at 1m concentration; all gases at 1 atmosphere pressure) a. 2Cr(s) + 3Cl2(g) = 2 Cr+3 + 6 Cl- b. NO3- + 2 H+ + Ag(s) = Ag+ + H2O + NO2(g) c. NO3- + 4 H+ + 3 Ag(s) = 3 Ag+ + NO(g) +2H2O d. Cl2(g) + 2 Br- = 2 Cl- + Br2

Molecular compounds of low molecular weights tend to be gases at room temperature. Which of the following is most likely not a gas at room temperature? a. Cl2 b. HCl c. LiCl d. H2

A liquid will “wet” a surface if: a. the liquid has a lesser density than the surface b. the forces between the liquid molecules are weak c. the liquid has a low vapor pressure d. the forces between the molecules and the surface are greater than the forces between the molecules of the liquid

The series in which the electrode potentials of metals are arranged in an order is known as: a. electrical conductivity series b. electrode potential series c. electrochemical series d. chemical affinity series

When an iron wire is immersed in an acidic solution of CuSo4, the blue color of the solution is lost after some time. This is due to a. reduction of Cu++ b. oxidation of CuSO4 c. formation of double complex between iron and copper sulfate d. formation of a colorless salt of Cu++

If 0.200 liter of 0.100 M NaCl are electrolyzed until the OH- concentration is 0.0500M, how many moles of Cl2 gas are produced? a. 5.00 x 10-3 mole b. 1.00 x 10-2 mole c. 5.00 x 10-2 mole d. 1.00 x 10-1 mole

Which of the following instruments makes use of the standard electrode potentials and the variation of electrode potential with concentration? a. Polarimeter b. pH meter c. Electrophorous d. Electrophotometer

Gaseous mixtures _________. a. can only contain molecules. b. are all heterogenous. c. can only contain isolated atoms. d. are all homogenous.

Of the following, ____________ is a correct statement of Boyle’s law. a. PV = constant b. P/V = constant c. V/P = constant d. V/T = constant

The mathematical statement of Gibb’s phase rule is a. F = C-P+2 b. C = F-P+2 c. C = F-P+1 d. P = C+F+2

The temperature at which the vapor pressure of a liquid equals the external pressure is called the : a. boiling point b. critical point c. melting point d. sublimation point

A gas is considered “ideal” if ___________. a. it is not compressible b. one mole of it occupies exactly 1 liter at standard temperature and pressure. c. it can be shown to occupy zero volume at 0degC d. its behavior is described by the ideal gas equation.

The energy of molecules of a gas: a. is dependent on concentration b. is distributed over a wide range at constant temperature c. is the same for all molecules at constant temperature d. increases with a decrease in temperature

The magnitude of the individual half cell potentials are given (i) CO2+ + 2e = CO 0.28V (ii) Hg2+ + 2e = 2Hg 0.78V when both the half cells (a) and (b) are connected with SHE, the metallic electrode Co is found to be –ve and Hg electrode is found to be +ve. The correct sign for the electrode potentials will be: a. +ve for half cell (I) b. +ve for half cell (ii) c. –ve for half cell (ii)

When a liquid is in dynamic equilibrium with its vapor at a given temperature, the following conditions could exist: (I) There is no transfer of molecules between liquid and vapor (II) The vapor pressure has a unique value (III) The opposing processes, (liquid to vapor) and (vapor to liquid), proceed at equal rates (IV) The concentration of vapor is dependent on time Which of the above choices are applicable? a. I b. II and III c. I, II, and III d. II and IV

If aqueous Cu SO4 is electrolyzed for one minute with a current of 2.00 ampere, the volume of ozygen produced at STP at the anode is a. 3.10 x 10-4 liter b. 6.96ml c. 1.16 x 10-4 liter d. 1.16 ml

a liquid will “wet” a surface if: a. the liquid has a lesser density than the surface b. the forces between the liquid molecules are weak c. the liquid has a low vapor pressure d. the forces between the molecules and the surface are greater than the forces between the molecules of the liquid

Four colorless salt solutions are placed in separate test-tubes and a strip of copper is dipped in each.. which solution finally turns blue? a. Pb (NO3)2 b. Zn (NO3)2 c. AgNO3 d. Cd (NO3)2

Magnesium cannot displace from solution the ions of a. sodium b. copper c. lead d. gold

Of the following, only ______ is impossible for an ideal gas. a. V1/T1 = V2/T2 b. V1T1 = V2T2 c. V1/V2 = T1 / T2 d. V1/V2 = T1/T2 = 0

Which of the following does NOT describe the critical point of a liquid? a. The temperature and pressure at which a liquid’s meniscus disappears b. The point where the vapor pressure curve intersects the fusion temperature c. The highest temperature at which a liquid can exist d. The temperature and pressure at which a liquid and its vapor are identical e. The highest temperature at which it is possible to obtain a liquid form its vapor by increasing pressure

Consider two beakers, beaker A containing 50 mL of liquid U and beaker B 50 mL of liquid U and R. The boiling point of A is 90OC and that of B is 102OC. Which of the following statements is correct? a. A will evaporate faster than B b. B will evaporate faster than A c. Both A and B will evaporate at the same time d. Insufficient data to answer the question

The Ksp expression for a saturated solution of Ca3(PO4)2 is a. Ksp = [Ca2+][PO43-] b. Ksp = [Ca2+]3[PO43-]2 c. Ksp = [3Ca2+][2PO43-] d. Ksp = [3Ca2+]3[2PO43-]2

Substance X has 13 protons, 14 neutrons and 10 electrons. Determine its identity. a. 27 Mg b. 27 Ne c. 27 Al3+ d. 27 Al

The Mn is titrated directly with KMnO4 in a solution kept neutral with ZnO (Mn++ + MnO4- + ZnO = MnO2 + Zn++). In this case, the oxidation number of manganese is a. 5 b. 6 c. 3 d. 2

The equilibrium constant expression for a sulfurous acid is a. Ka = [H+][HSO3 -] b. Ka = [2H+][SO3 2-] / [H2SO3] c. Ka = [H+][HSO3 -] / [H2SO3] d. Ka = [H+][SO3 2-] / [H2SO3]

In the analysis of a sample of feldspar weighing 0.500 g, a mixture of KCl + NaCl is obtained weighing 0.1180 g. subsequent treatment with silver nitrate furnishes 0.2451 g of silver chloride. What is the percentage of K2O in the sample? a. 89.5% b. 25.5% c. 10.5% d. 3.67%

An atom of atomic number 53 and a mass number 127 contains how many neutrons? a. 53 b. 74 c. 127 d. 180

Which of the following ions could be added to an aqueous mixture containing Pb2+ and Ba2+ to separate the ions by precipitating one of them? a. I- b. NO3- c. PO4^3- d. SO4^2-

In redox reaction, reduction of MnO4- to Mn+2 requires the presence of a/an a. base b. salt c. acid d. catalyst

A salt forms in the reaction between HF(aq) and NaOH(aq). What is the net ionic equation for its hydrolysis? a. NaF(aq) ⇌ Na+(aq) + F-(aq) b. F-(aq) + H2O(aq) ⇌ HF(aq) + OH-(aq) c. HF(aq) + H2O(l) ⇌ H3O+(aq) + F-(aq) d. HF(aq) + NaOH(aq) ⇌ NaF(aq) + H2O(l)

In a saturated solution, the rate of dissolving is a. equal to zero b. ess than the rate of crystallization c. equal to the rate of crystallization d. greater than the rate of crystallization

Which of the following is a correctly balanced reduction half-reaction? a. 2HCN + 2e- = C2N2 + 2H+ b. 2Sb + 3H2O + 6e- = Sb2O3 + 6H+ c. NO3- + 3H+ + 3e- = HNO2 + H2O d. Sb2O5 + 6H+ + 4e- = 2Sb(OH)2+ + H2O

A 0.500 g sample of impure magnetite (Fe3O4) is converted by chemical reactions to Fe2O3, weighing 0.4110 g. What is the percentage of Fe3O4 in the magnetite? a. 79.46% b. 37.15% c. 21.06% d. 89.21%

Which of the following salt solutions is acidic? a. NaBr b. FeCl3 c. LiCN d. NaHCO3

Calculate the molarity of NaOH solution if 12.25 mL was used to titrate 0.2615 gram of primary standard KHP (204.22 g/mol). a. 0.1045 b. 0.1354 c. 0.2509 d. 0.1697

A sample consisting Na2CO3, NaOH and inert matter weighs 1.179 grams. It is titrated with 0.2239 M HCl with phenolphthalein as indicator, and the resulting solution became colorless after the addition of 45.62 mL. Methyl orange is then added and 12.85 mL more of the acid is needed for the color change. What is the percentage of Na2CO3 in the sample? a. 24.89% b. 64.95% c. 76.12% d. 25.87%

Which of the following methods is NOT used for the determination of halides? a. Volhard b. Mohr c. Fajans d. Liebig

Calculate the molar concentration of a solution that is 30% by wt ammonium nitrate and has a specific gravity of 1.1252. a. 4.22 M b. 6.85 M c. 5.27 M d. 3.08 M

How much 0.600 N base must be added to 750 mL of a 0.200 N base in order for the solution to be 0.300 N? a. 240 mL b. 550 mL c. 250 mL d. 900 mL

The solubility of a solute is best determined from which type of solution? a. a saturated solution b. an unsaturated solution c. any solution at 25degC d. a supersaturated solution

Which equation represents a redox reaction? a. Pb2+ + 2Cl- → PbCl2 b. CaO + CO2 → CaCO3 c. Mg + 2HCl → MgCl2 + H2 d. HCl + NaOH → NaCl + H2O

What is the conjugate acid of the base HAsO42-? a. AsO4 3- b. H2AsO4 2- c. H2AsO4 - d. H3AsO4

In the titration involving dichromate in excess of iodine, Cr2O7- + I- + H+ = Cr+3 + I2 + H2O, it follows that dichromate liberates what amount of iodine? a. 2 b. 3 c. 5 d. 6

What two substances are produced when Cr and 1.0 M MnO4- react in a basic solution? a. Mn2+ and Cr3 b. MnO2 and Cr3+ c. Mn2+ and Cr2+ d. MnO2 and CrO42-

What is the oxidation number of carbon in the oxalate radical? a. +6 b. +2 c. +3 d. +4

What is the pH of 0.256 M ammonium chloride? Kb = 1.8 x10-5 a. 2.64 b. 9.90 c. 11.36 d. 4.92

The addition of a crystal of NaClO3 to a solution of NaClO3 causes additional crystals to precipitate. The original solution was a. unsaturated b. saturated c. dilute d. supersaturated

Consider the following unbalanced equation for a redox reaction in acidic solution: Br- + BrO3- = Br2 . What is the equation for the balanced reduction half-reaction? a. 2Br = Br2 + 2e- b. 5e- + 6H+ + 2BrO3- = Br2 + 3H2O c. 2Br- + 2e- = Br2 d. 10e- + 12H+ + 2BrO3- = Br2 + 6H2O

What mass in grams of sodium acetate must be dissolved with 500 mL of 0.100 M acetic acid to make a 2L of a buffer solution of pH = 5? Ka = 1.8 x10-5 a. 2.28 b. 7.19 c. 7.38 d. 2.12

The following primary standards can be used for the standardization of acids except HgO CaCO3 KH(IO3)2 Na2CO3

Consider the redox reaction: 3SO2 + 3H2O + ClO3- → 3SO42- + 6H+ + Cl-. The reduction half-reaction is a. ClO3- + 6H+ → Cl- + 3H2O + 6e- b. ClO3- + 6H+ + 6e- → Cl - + 3H2O c. SO2 + 2H2O → SO42- + 4H+ + 2e- d. SO2 + 2H2O + 2e- → SO42- + 4H+

In standardizing a solution of NaOH against 1.431 g of KHP (KC8H5O4), the analyst uses 35.50 mL of the alkali and has to run back with 8.25 mL of acid (1 mL=10.75 mg NaOH). What is the molarity of the NaOH solution? a. 0.2118 b. 0.2044 c. 0.7831 d. 0.2598

How many grams of potassium dichromate, K2Cr2O7, constitute its gram equivalent weight as an oxidizing agent? a. 0.03161 g b. 0.04903 g c. 0.09806 g d. 0.29418 g

Which of the following is not a correct analytical method – titrant pair? a. Mohr - AgNO3 b. Fajans - AgNO3 c. Volhard - AgNO3 d. Liebig - AgNO3

A substance that causes the reduction of another substance is a/an a. reductant b. oxidant c. neither d. catalyst

Which procedure is most likely to increase the solubility of most solids in liquids? a. stirring b. pulverizing the solid c. heating the solution d. increasing the pressure

If used in neutral or alkaline solution in titration, permanganate is reduced to a. Mn++ b. MnO2 c. Mn6+ d. Mn3O4

In the preparation of standard potassium iodate solution containing excess iodine, the gram equivalence of iodine per mole of potassium iodate is a. 6 b. 3 c. 2 d. 5

Fajans method utilizes what indicator? a. starch b. ferric thiocyanate c. dichloroflurorescein d. erichrome black T

Which equation represents a neutralization reaction? a. Pb2+(aq) + 2Cl-(aq) → PbCl2(s) b. HCl(aq) + NH3(aq) → NH4Cl(aq) c. BaI2(aq) + MgSO4(aq) → BaSO4(s) + MgI2(aq) d. MnO4-(aq) + 5Fe2+(aq) +8H+(aq) → Mn2+(aq) + 5Fe3+(aq) + 4H2O(l)

A strong oxidizing agent has a a. weak attraction for electrons b. strong attraction for electrons c. weak ability to become reduced d. strong ability to become oxidized

What is the percentage of MnO2 in a pyrolusite ore is a sample weighing 0.400 g is treated with 0.6000 g of pure H2C2O4.2H2O and dilute H2SO4 and after reduction has taken place (MnO2 + H2C2O4 + 2H+ = Mn++ + 2 CO2 + 2H2O), the excess oxalic acid requires 26.26 ml of 0.100 N KMnO4 for titration? a. 30.015% b. 75.00% c. 6.63% d. 80.03%

When a magnesium atom participates in a chemical reaction, it is most likely to a. lose 1 electron b. gain 2 electrons c. gain 1 electron d. lose 2 electrons

Which condition is essential to prepare a saturated solution of an ionic salt? a. excess solute b. any amount of solute c. a temperature of 25degC d. fixed volume of solvent

A sample of soda ash (impure Na2CO3) is titrated with 0.500 N H2SO4. If the sample weighs 1.100 g and requires 35.00 mL of the acid for complete neutralization, what is the percentage of Na2CO3 in the ash assuming no other active component to be present? a. 84.32% b. 90.32% c. 35.00% d. 56.21%

Common indicator for iodimetric titrations a. methyl orange b. pulverizing the solid c. heating the solution d. increasing the pressure

Oxalic acid dihydrate is a pure, stable, crystalline substance. Which of the following describes one of its uses in acid-base titrations? a. buffer b. primary standard c. indicator d. acid anhydride

How may grams of potassium binoxalate, KHC2O4.H2O, constitute its gram equivalent weight as a reducing agent? a. 73.07 g b. 146.14 g c. 63.03 g d. 63.55 g

Identify a conjugate pair from the equilibrium provided: PO43- + HCO3- ⇌ HPO42- + CO32- a. CO3^2- and HPO4^2- b. PO4^3- and HPO4^2- c. PO4^3- and HCO3^- d. HCO3^- and HPO4^2-

Identify an environmental problem associated with acid rain. a. increasing the pH of lakes b. chemical decomposition of rainwater c. the green house effect d. metals leaching from river rocks accumulating in lakes

The concentration at which some chemical is toxic, used where the amount ingested cannot be measured, such as in evaluating the quality of air. a. LDC50 b. LD50 c. Toxicity d. PM10

The water sample from a sewage plant had a 20-day BOD of 400 mg/L at 20degC. What was the expected 5-day demand? a. 404 ppm b. 304 ppm c. 276 ppm d. 196 ppm

Which of the following sources is responsible for maximum air pollution? a. industrial chimney exhaust b. forest fire c. automobile exhaust d. photochemical oxidation organic matter

Which of the following statement is true about brittle fracture? a. high temperature and low strain rates favour brittle fracture b. many metals with hexagonal closed packed crystal structure commonly show brittle fracture c. brittle fracture is always preceded by noise d. cup and cone formation is characteristic for brittle materials

Determine the approximate density of a high-leaded brass that has a composition of 64.5 wt% Cu ( ρ = 8.94 g/cc ), 33.5 wt% Zn (ρ = 7.13 g/cc) and 2 wt% Pb (ρ = 11.35 g/cc). a. 7.89 g/cc b. 9.12 g/cc c. 10.11 g/cc d. 8.27 g/cc

High bonding energy is associated to a. smaller volume b. high density c. loosely packed d. A & B

Aluminum has an FCC crystal structure and an atomic radius of 0.1431 nm. What would be its interplanar spacing for the (110) set of planes a. 0.2862 nm b. 0.1431 nm c. 0.4040 nm d. 0.3122 nm

What type of glass exhibit resistance to heat and chemical? a. soda lime b. borate glass c. silica glass d. NOTA

A global treaty that aims to protect human health and the environment from persistent organic compounds. a. montreal protocol b. earth summit c. kyoto protocol d. stockholm convention

Denitrification in an activated sludge plant involves a. the oxidation of ammonia to nitrates b. high concentrations of DO in the mixed liquor as it settles in the secondary clarifier c. the biological oxidation of nitrates to nitric oxide d. the biological reduction of nitrates to nitrogen gas

Grain mostly found near the wall of the crystal a. columnar b. equiaxed c. equiaxial d. perpendicular

A coarse grained steel a. is less tough and has a greater tendency to distort during heat transfer b. is more ductile and has a less tendency to distort during heat transfer c. is less tough and has a less tendency to distort during heat treatment d. is more ductile and has a greater tendency to distort during heat transfer

Amorphous material is one a. in which atoms align themselves in a geometric pattern upon solidification b. in which there is no definite atomic structure and atoms exist in a random pattern just as in a liquid c. which is not attacked by phosphorous d. which emits fumes on melting

Compute the concentration of lithium (in wt%) that, when added to aluminum, will yield an alloy having a density of 2.55 g/cc. ( ρ=0.534 g/cc for Li and ρ=2.71 g/cc for Al) a. 1.112 wt% b. 1.537 wt% c. 2.981 wt% d. 3.12 wt%

Radiation wastes usually measured in curies/L is a. high level wastes b. intermediate level wastes c. low level wastes d. none

The transport of dangerous goods by rail is a. fermentation b. flocculation c. condensation

Copper in nickel is an example of _____ solid solution. a. substitutional b. vacancy c. interstitial d. NOTA

The float blanket in a DAF unit appears well flocculated and concentrated. Too low a flight speed would likely result in a. using excessive amounts of air b. float solids that are too thick c. poor thickener underflow quality d. too low an air to solid ratio

A sample of well water contains 140 gm/m3 Ca2+ ions and 345 g/m^3 Na+ ions. The hardness of the sample of water, expressed in terms of equivalent CaCO3 in g/m^3 is (assuming atomic masses of Ca :40, Na : 23, C : 12, O : 16) a. 140 b. 350 c. 345 d. 485

What volume of wastewater sample was mixed with dilution water containing 11.50 ppm of dissolved oxygen if the dissolved oxygen contents of the mixture before and after 5 days of incubation at 200C are 10.0 ppm and 7.0 ppm respectively? The wastewater sample had an initial dissolved oxygen content of 2 ppm. a. 27.4 mL b. 37.4 mL c. 4.4 mL d. 57.4 mL

α-iron has a BCC crystal structure and an atomic radius of 0.1241 nm. Determine its lattice parameter. a. 0.3510 nm b. 0.2884 nm c. 0.0931 nm d. 0.4040 nm

States that the total electrical resistivity is equal to the sum of the thermal impurity and deformation resistivity contributions. a. Matthiessen’s rule b. Ohm's law c. Stress and strain law d. Fick's law

The most common cause of acidity in water is a. carbon dioxide b. oxygen c. hydrogen d. nitrogen

Sea water contains 3% total solids, 80% of which is pure soldium chloride. How many ppm of sodium chloride are there in sea water? a. 20 000 ppm b. 24 000 ppm c. 26 000 ppm d. 30 000 ppm

Calculate the theoretical density of magnesium that has an HCP crystal structure and a radius of 1.60 x 10^-8 cm. a. 1.75 g/cc b. 8.82 g/cc c. 1.38 g/cc d. 1.60 g/cc

Plastic deformation means a. reversible deformation b. irreversible deformation c. expansion d. compression

Charged electrons, more penetrating than alpha particles, requires some level of shielding a. Alpha b. Beta c. Gamma d. none

Usually hold wastewater at low velocity and recommended for small populations a. preliminary clarifiers b. secondary clarifiers c. septic tank d. advance method

Ground water is usually free from a. suspended impurities b. dissolved impurities c. both of the choices d. none of the choices

The settling velocity of a particle in a sedimentation tank is increased a. if particle size is decreased b. the depth of the tank is decreased c. the surface area of tank is increased d. none of the choices

This can be used as the total treatment system for municipal wastewater. a. shallow pond b. facultative pond c. deep pond d. lagoon

Measures the biological injury that would result from the absorption of nuclear radiation. a. Sievert b. Roentgen c. REM d. Gray

Which of the following has a fine gold color and is used for imitation jewelry? a. silicon bronze b. aluminum bronze c. gun metal d. Babbit metal

Determine the radius of an iridium atom, given that Ir has an FCC crystal structure with a density of 22.4 g/cm3. a. 0.009 nm b. 0.136 nm c. 0.009 cm d. 0.136 cm

Which of the following air pollutants destroys rubber? a. CFCs b. Ozone c. CO d. NOx

The permissible BOD for domestic water supply in ppm a. 50 b. 1000 c. 500 d. 100

Which one of the following statement is TRUE regarding trickling filters? a. the TF process may be improved significantly by the addition of an aerated solids contact which improves the settling of the sloughing b. letting a TF dry out is a common strategy for controlling psychoda c. reducing recirculation to a TF is an appropriate strategy to promote the nitrification of ammonia d. when calculating the organic loading rate to a TF, one should include the BOD of the recirculated flow in this calculation

Brass is an example of a. substitutional solid solution b. interstitial solid solution c. intermetallic compounds d. all of the above

Based from the previous problem, determine the interplanar spacing for the (310) set of planes. a. 0.0912 nm b. 0.0931 nm c. 0.0112 nm d. 0.1209 nm

Blood hemoglobin has a CO affinity __________ greater than its affinity for oxygen and thus CO combines with hemoglobin and can cause death. a. 120 times b. 210 times c. 220 times d. 250 times

Calculate the radius of a vanadium atom in a BCC structure having a density of 5.96 g/ cm3. a. 0.243 nm b. 0.198 nm c. 0.157 nm d. 0.132 nm

This addresses acute problems caused by improper hazardous waste disposal or accidental discharge & cleanup of old sites. a. TOSCA b. RCRA c. CERCLA d. EPA

A property of glasses which is a disadvantage in processing a. mechanically brittle b. small bond gap c. high melting point d. promote slips and dislocation

A 35 ml sample of wastewater is diluted to a volume of 300 mL, after which a 5 day incubation resulted to a dissolved oxygen content of 4.55 mg/L. Calculate the initial DO of the diluted sample if the 5 day BOD is 30 ppm. a. 5 mg/L b. 8 mg/L c. 12 mg/L d. 15 mg/L

Tungsten has a BCC crystal structure for which R = 0.137 nm, determine its density. a. 19.3 g/cc b. 21.1 g/cc c. 16.8 g/cc d. 18.1 g/cc

The volume of the titanium unit cell in HCF structure is a. 1.058 x 10-^28 m3/ unit cell b. 1.112 x 10^-28 m3/ unit cell c. 0.158 x 10^-28 m3/ unit cell d. 1.105 x 10^-28 m3/ unit cell

Calculate the density of iron in its BCC form whose radius is 0.124 x 10^-7 cm. a. 5.67 g/cc b. 13.22 g/cc c. 8.21 g/cc d. 7.90 g/cc

Dissolved oxygen content in river water is around _____ ppm. a. 5 b. 100 c. 250 d. 500

The capacity of a material to absorb energy when it is deformed and upon unloading the energy is recovered. a. ductility b. resilience c. toughness d. hardness