day1 Flashcards
The distance of the Earth to the most remote normal galaxy is calculate to be
9x10^25 m
distance from earth to nearest known galaxy (Andromeda)
2x10^22 m
distance from Earth to most remote known Quasar
1.4x10^26 m
Distance from Earth to nearest known star (Proxima Centauri)
4x10^16 m
determination of nitrogen based on the conversion of organic nitrogen to ammonia, which is then separated by distillation and determined by titration
kjeldahl method
which of the following pairs will form a buffer solution in the course of a titration?
a. nitric acid, sodium hydroxide
b. sulfuric acid, potassium hydroxide
c. acetic acid, sodium hydroxide
d. hydrochloric acid, potassium hydroxide
c. acetic acid, sodium hydroxide
When a can of soda is opened and CO2 is released to the atmosphere, what is the resultant pH of the soda?
a. decreases
b. increases
c. the same
d. all these
b. increases
define a salt in terms of acid and base
a. a salt is a compound that follows Le Chatelier’s Principle in reactions with other compounds
b. all of these
c. a salt is a compound formed when the nucleus of a hydrogen tom enters a quantity of water
d. a salt is a compound (other than water) produced by the reaction of an acid and a base
d. a salt is a compound (other than water) produced by the reaction of an acid and a base
when benzoic acid dissolves in water, it partially reacts with water and ionizes to form benzoate and hydronium ions. in this reaction, what is the conjugate acid?
a. benzoate ions
b. hydronium ions
c. water
d. benzoic acid
b. hydronium ions
water at room temperature usually has a slightly acidic pH. this is largely attributed to what compound(s)?
a. sulfuric acid
b. dissolved metals
c. carbonic acid
d. nitric acid
c. carbonic acid
are galvanic cells and electrolytic cells the same? why?
a. no, because galvanic cells are electrochemical cells in which chemical cells occur simultaneously; while in electrolytic cells. the chemical reaction is caused by an externally applied potential difference.
b. no, because galvanic cells need a constant supply of electricity while electrolytic cells depend on intermittent source of power
c. yes, because they are both electrochemical cells and their uses are common to each other
d. yes, because galvanic cells and electrolytic cells are both electrochemical cells
a. no, because galvanic cells are electrochemical cells in which chemical cells occur simultaneously; while in electrolytic cells. the chemical reaction is caused by an externally applied potential difference.
what is the significance of colligative property in physical chemistry?
a. it refers to the freezing point depression, boiling point elevation osmotic pressure and lowering of the vapor pressure by a nonvolatile solute.
b. it refers to the temperature, pressure and energy of fusion of volatile solutes in phase equilibrium
c. it refers to the non-existence of pressure among molecules within the solute
d. it refers to the temperature differentials exhibited by non-volatile solutes in reactions
a. it refers to the freezing point depression, boiling point elevation osmotic pressure and lowering of the vapor pressure by a nonvolatile solute.
which of the following statements is true?
a. trouton’s rule fails for highly polar liquids
b. it is impossible to go from vapor phase to liquid phase without condensation
c. for C compounds and P phases, there are a total of CP intensive variables to be specified
d. at high pressures, the latent heat of vaporization is a measure of the strength of the intermolecular forces of the liquid
a. trouton’s rule fails for highly polar liquids
among the following, which compound will produce the lowering of the vapor pressure of a solution?
a. sucrose, c12h22o11
b. aluminum chloride, alcl3
c. table salt, nacl
d. sodium sulfate, na2so4
a. sucrose, c12h22o11
when a solute is introduced to a liquid system the entropy of the said system
a. increases
b. decreases
c. stays the same
d. can’t be determined
a. increases
in a process involving osmosis, at equilibrium, the chemical potential of the pure solvent side should be _____ the chemical potential of the side with solute
a. less than
b. more than
c. equal to
d. can’t be determined
c. equal to
all colligative properties stem from the ____ of the chemical potential of the liquid solvent as a result of the presence of the solute
a. reduction
b. change
c. enlargement
d. a or b or c, depending on the identities of the solute and solvent
a. reduction
for miscible systems, the boiling point of the solution is
a) lower than the boiling point of the liquid with the lower boiling point
b. between the boiling points of the two liquids
c. above the boiling point of the liquid with the higher boiling point
d. cannot be determined
b. between the boiling points of the two liquids
the coexistence curve where the plot of pressure versus temp along which the two phases coexist was shown by clausius clapeyron. what did clausius postulate?
a) the clapeyron equation was simplified by assuming that the vapor obeys the ideal gas law and by neglecting the molat volume of the liquid in comparison with the molar volume of the gas
b. the clausius-clapeyron equation does not apply to this situation
c. the clausius-clapeyron theory is applicable only for vaporization and sublimation condition
d. both scientists apply their postulates to linear and curvilinear representation
a) the clapeyron equation was simplified by assuming that the vapor obeys the ideal gas law and by neglecting the molat volume of the liquid in comparison with the molar volume of the gas
what is the clapeyron equation?
a. any of these
b. it postulates that the colligative properties, freezing point depression, boiling point elevation, osmotic pressure, and vapor pressures are all dependent on the number f particles in the solution and any change thereof is described
c. it postulates that if two components systems consisting of solid and liquid phases are miscible in the liquid state and immiscible in the solid state, only the pure solid systems will separate out on cooling solutions
d. it postulates that if the temperature and pressure are both change in such a way as to keep the chemical potentials of two phases equal to each other, the rates of change are given by the equation.
d. it postulates that if the temperature and pressure are both change in such a way as to keep the chemical potentials of two phases equal to each other, the rates of change are given by the equation.
the clausius-clapeyron equation does NOT apply to
a) S-V equilibrium
b. L-V equilibrium
c. S-L equilibrium
d. None of these
c. S-L equilibrium
the clapeyron equation gives the slope
a) dv/dt
b) dt/dp
c) dt/dv
d) dp/dt
d) dp/dt
it is the property of a fluid that is caused by shearing effect of a fluid layer moving past another layer
a. density
b. viscosity
c. flow.
d. compressibility
b. viscosity
which of the following does not have a zero enthalpy of formation at 298.15 K
a. Li (g)
B. He (g)
c. Hg (l)
d) Br2 (l)
a. Li (g)
choose the process that occurs with a decrease in entropy
a. freezing of water
b. boiling of water
c. dissolving salt in water
d. sublimation of dry ice
a. freezing of water
define entropy
a. entropy is a function of the state of the system and determines whether a physical change or chemical reaction can occur simultaneously in a closed system
b. entropy is the opposite of enthalpy
c. entropy determines the time required for a reaction to proceed and complete
d. all of these
d. all of these
an adiabatic process is one in which the system under investigation is thermally isolated so that there is no exchange of heat with the surroundings. thus, the work done on a closed system in an adiabatic process is ____
a. equal to zero
b. not equal to the exchange of heat with surroundings
c. equal to the increase in internal energy of the system
d. not equal to the increase in internal energy of the system
c. equal to the increase in internal energy of the system
the fugacity of a real gas is equal to:
a. the pressure of an ideal gas which has the same chemical potential as the real gas
b. the pressure of a real gas which has the same chemical potential as the ideal gas
c. the chemical potential of an ideal gas which has the same pressure as the real gas
d. the chemical potential of a real gas which has the same pressure as the ideal gas
a. the pressure of an ideal gas which has the same chemical potential as the real gas
the equilibrium intensive state of a system is described by specifying the temp pressure and
a. mole fractions
b. number of moles
c. volume
d. chemical potential
a. mole fractions
the general statement of the Third Law of Thermodynamics is attributed to
a. Nikolaus Otto
b. Jacobus Clapeyron
c. William Clausius
d. Walther Nernst
d. Walther Nernst
Which of the following statements is/are true?
- the criterion of equilibrium at constant temp and pressure id dG= 0
- for a reversible process, ds=dQ/T
a. 1 only
b. both 1 and 2
c. 2 only
d. none of the above
b. both 1 and 2
heat required to raise the temp of 1 lbm of water by 1F
a. calorie
b. BTU
c. specific heat
d. heat capacity
b. BTU
the amount of heat absorbed when co2 gas reacts with a solid CaO to form solid CaCO3 is measured in a bomb calorimeter. the data obtained give a direct measure of
a. delta U
b. VdeltaP
c. delta H
d. Cp
a. delta U
if the entropy of a system decreases, the entropy of its surroundings
a. must always increase
b. must always decrease
c. may increase or decrease
d. not enough information to answer the question
a. must always increase
increasing the temperature of the cold reservoir ___ the carnot efficiency
a. increases
b. decreases
c. does not change
d. NOTA
b. decreases
An isentropic process is
a. isothermal and adiabatic
b. reversible and isothermal
c. reversible and adiabatic
d. reversible and isochoric
c. reversible and adiabatic
which of the following is not conserved in any process?
a. mass
b. energy
c. momentum
d. entropy
d. entropy
a sample of an ideal gas has an internal energy of U and is then compressed to 1/2 of its original volume while the temperature stays the same. what is the new internal energy of the ideal gas in terms of U?
a. U
b. U/2
c. U/4
d. 2U
a. U
which of the following is a characteristic of an adiabatic process?
a. delta U = 0
b. W = 0
c. Q=0
d. delta V =0
c. Q=0
the internal energy of an ideal gas depends on
a. volume
b. absolute temperature
c. pressure
d. number of moles
c. pressure
this is the pressure exerted by the gas molecules that are in equilibrium with the liquid
a. partial pressure
b. atmospheric pressure
c. total pressure
d. vapor pressure
d. vapor pressure
when gas molecules collide, they experience _ collision
a. perfectly elastic
b. imperfect elastic
c. perfectly inelastic
d. imperfect inelastic
a. perfectly elastic
which of the following is false with KMT?
a. gas molecules move in random motion
b. due to collision of gas molecules with each other, some kinetic energy is lost
c. the temperature of the whole system does not change with time
d. the size of the molecules are negligible
b. due to collision of gas molecules with each other, some kinetic energy is lost
for a real gas, what causes the deviation from the ideal pressure at a molecular level?
a. energy is lost for each collision against the sides of the container
b. energy is lost due to the collision of molecules with one another
c. intermolecular forces of attraction of the molecules with one another
d. molecules randomly hit the sides of the wall with less force than usual
c. intermolecular forces of attraction of the molecules with one another
an ideal gas will only be considered in the following operating parameters
a. high temp, high pressure
b. high temp, low pressure
c. low temp, high pressure
d. low temp, low pressure
b. high temp, low pressure
which of the following is false regarding absolute zero?
a. all molecules will stop moving
b. absolute zero can be achieved
c. temp is 0K
d, temp is 0R
b. absolute zero can be achieved
which among the following radioactive nuclides is often attributed as the greatest source of radiation that affects most of the population?
a. strontium-90
b. americium-241
c. polonium-218
d. radon-222
d. radon-222
which among the following statements regarding nuclear fission is false?
a. nuclear fission is a nuclear reaction in which a heavy nucleus splits into lighter nucleus and energy is released
b. a series of self-sustaining nuclear fissions is called a nuclear chain reaction
c. nuclear fission is the main proponent of nuclear power plants, atomic bombs, and hydrogen bombs
d. critical mass is the minimum amount of a fissionable material that can cause a nuclear chain reaction
c. nuclear fission is the main proponent of nuclear power plants, atomic bombs, and hydrogen bombs
in which among the following can a Cherenkov Radiation be observed?
a. in the water surrounding the core of a nuclear reactor
b. in the mushroom cloud produced after a hydrogen bomb explosion
c. in a particle accelerator after the bombardment of two nuclides
d. in the sun’s corona during solar eclipse
a. in the water surrounding the core of a nuclear reactor
determine the number of days it will take for 1 mg of Rubidium to decay to 0.6 mg
a.132
b. 98
c. 64
d. 211
c. 64
which among the following is the phosphor of scintillation counter intended for the detection of gamma radiation?
a. zinc sulfide
b. metastable technetium-99
c. NaI crystals containing Thallium (II) Iodide
d. Buckminsterfullerene
c. NaI crystals containing Thallium (II) Iodide
which among the following can detect the neutrons produced by U-235 undergoing nuclear fission?
a. A geiger counter containing fluorine gas
b. a scintillation counter containing zinc sulfide and xenon
c. a geiger counter containing argon and boron trifluoride
d. a scintillation counter containing tungsten carbide
c. a geiger counter containing argon and boron trifluoride
which among the following radioactive decay series does not occur naturally?
a. actinium series
b. uranium series
c. neptunium series
d. thorium series
c. neptunium series
protium is a/an ____ of hydrogen while protium, deuterium, and tritium comprise the hydrogen ____
a. isotope, isotopes
b. nuclide, nuclides
c. nuclide, isotopes
d. isotope, nuclides
c. nuclide, isotopes
which among the following scientists discovered radioactivity?
a. marie curie
b. henri becquerel
c. otto hahn
d. ernest rutherford
b. henri becquerel
positive electron
positron
has a higher penetrating power than gamma rays
neutrons
ghost particle
neutrino
which of the acid combination is the dominant composition of acid rain?
a. nitric acid and carbonic acid
b. nitric acid and sulfuric acid
c. carbonic acid and sulfuric acid
d. none of the above
b. nitric acid and sulfuric acid
the rate at which temp changes with altitude is called
a. temperature change
b. thermal rate
c. lapse rate
d. vertical rate
c. lapse rate
pick out the wrong statement
a. the concentric atmosphere layer just above troposphere is called stratosphere, which is rich in ozone
b. mesosphere is characterized by very low atmosphere pressure and low temp
c. troposphere is a dusty zone containing water vapor and clouds
d. the radio waves used in long distance radio communication are reflected to earth by stratosphere
d. the radio waves used in long distance radio communication are reflected to earth by stratosphere
it is an odorless gas that is lethal to humans with exposure as short as a few minutes to concentrations exceeding 5000 ppm. it reacts with hemoglobin in the blood rendering the latter incapable of carrying oxygen to the body
a. carbon monoxide
b. hydrogen supplied
c. sulfur dioxide
d. sulfur trioxide
a. carbon monoxide
collective term for the initial POPS identified by the stockholm convention
a. Dirty 12
b. 12 POPS
c. Dirty Dozens
d. EDCs
c. Dirty Dozens
a global treaty that aims to diminish and eventually phase out chlorofluorocarbons
a. stockholm convention
b. kyoto protocal
c. montreal protocol
d. none of these
c. montreal protocol
regulate emmisions of greenhouse gases
kyoto protocol
aims to diminish and eventually phase out chlorofluorocarbons
montreal protocol
aims to protect human health and the environment from persistent organic pollutants
stockholm convention
“smokey mountain” is a typical example of a facility for solid waste. it is classified as
a. open dumping site
b. sanitary landfill
c. transfer station
d. material recovery facility
a. open dumping site
an act to control toxic substances and hazardous and nuclear wastes providing penalties for violation thereof
RA6969
ecological solid waste management act
RA 9003
clean air act of the philippines
RA 8749
A code for plastics used for food wrapping, trash bags, grocery bags and baby diapers
a. 2
b. 3
c. 4
d. 5
c. 4
water treatment that destroys disease-causing bacteria, nuisance bacteria, parasites and other organisms and removes soluble irons, manganese and hydrogen sulfide from water
a. disinfection
b. flocculation
c. chlorination
d. coagulation
c. chlorination
process whereby coarse matter of a certain size can be strained out of flowing water with the aid of bars, fines wires or rocks
a. screening
b. sedimentation
c. flotation
d. flocculation
a. screening
removal of all settleable particles rendered settleable under the influence of gravity, basically the theory of gravity under the influence of which all particles heavier than water tend to settle down
a. screening
b. flotation
c. sedimentation
d. flocculation
c. sedimentation
hard water can be softened by
a. letting the calcium or magnesium ions settle out
b. passing it through an ion exchanger
c. chlorination
d. filtration
b. passing it through an ion exchanger
type of wastewater treatment that employs physical and chemical treatment methods to remove or reduce a high percentage of suspended solids and toxic materials
a. primary treatment
b. secondary treatment
c. tertiary treatment
d. minor treatment
a. primary treatment
sum of all polyvalent cations
water hardness
a trace metal which causes itai-itai diseases is
a. cadmium
b. silver
c. mercury
d. chromium
a. cadmium
involves the accumulation of trace metals through each species of the food chain
a. biomagnification
b. denitrification
c. anaerobic respiration
d. eutrophication
a. biomagnification
it is phenomenon that results in the overabundance of algae growth in bodies of water. it is also the natural process of nutrient enrichment that occurs over time in a body of water
a. biomagnification
b. eutrophication
c. anaerobic respiration
d. thermal inversion
b. eutrophication
which of the following is not a physical characteristic of wastewater
a. odor
b. turbidity
c. color
d. hardness
d. hardness
in the determination of BOD, the reaction takes place in the dark because
a. the microorganisms are sensitive to light
b. oxygen is sensitive to light
c. the reaction is enhanced in the dark
d. algae may be present and produce oxygen
d. algae may be present and produce oxygen
in determination of BOD, the reaction takes place at
a. 20C
b. 30C
c. 40C
d. 50C
a. 20C
a measure of the amount of O2 needed to oxidize organics using strong oxidizing agents in acid media
chemical oxygen demand
a measure of the amount of o2 needed by microorganism to decompose biodegradation organics at a specified time, temp and ph
Biological oxygen demand
the color of wastewater containing little or no dissolved oxygen is
a. gray
b. black
c. brown
d. reddish brown
b. black
dissolved oxygen in water is reduced during
a. winter
b. summer
c. spring
d. autumn
b. summer
actual quantity of free o2 present in water
dissolved oxygen
a measure of the amount of o2 needed to oxidize completely an organic matter whose chemical formula is known
theoretical oxygen demand
the total solids in water are due to the presence of
a. suspended and dissolved solids
b. suspended and floating solids
c. colloidal and settleable solids
d. colloidal and bacterial load
a. suspended and dissolved solids
sodium ions contribute to which characteristics of the water
a. pH
b. color
c. hardness
d. total dissolved solids
d. total dissolved solids
which of the ff is not used in measuring turbidity
a. jackson turbidimeter
b. secchi disk depth
c. photoelectric colorimeter
d. none of these
c. photoelectric colorimeter
gas responsible for rotten egg odor of wastewater
a. ammonia
b. amines
c. mercaptans
d. hydrogen sulfide
d. hydrogen sulfide
navigable waters
class SD
water quality guidelines and general effluent standards
DAO No. 2016-08
Philippine Clean Water Act of 2004
RA9275
the electron-group geometry of h2o is
a. trigonal planar
b. trigonal pyramidal
c. bent
d. tetrahedral
d. tetrahedral
what is the molecular geometry of nh4
a. bent
b. trigonal pyramidal
c. tetrahedral
d. trigonal planar
c. tetrahedral
when light of sufficient energy shines on a metal, electrons are knocked off the surface of the metal. what is this phenomenon called?
a. electron harvesting
b. photoelectric effect
c. blackbody radiation
d. illumination
b. photoelectric effect
which among the following is the third gas that william ramsay isolated with morries travers?
a. argon
b. krypton
c. neon
d. xenon
d. xenon
who among the following proposed the idea correlating molecular geometry and valence electron pairs that would later become the valence shell electron pair repulsion or VSEPR theory?
a. Nevil Sidgwick
b. Herbert Powell
c. Ronald Nyholm
d. Ryutaro Tsuchida
d. Ryutaro Tsuchida
which element constituted the need of a new group in the original design of dmitri mendeleev’s periodic table
a. gallium
b. argon
c. mercury
d. tungsten
b. argon
the precision of knowing a particles momentum indicates that its loci would be impossible to determine is one way of interpreting which among the following
a. aufbau principle
b. pauli exclusion principle
c. compton effect
d. heisenberg principle
d. heisenberg principle
empirical formula of Human dna
C39H50O22N15P3
what properties of electrons are used in the operation of an electron microscope?
wave properties
only country that is named after an element
argentina
