CHEMISTRY FOR ENGINEERS Flashcards
Boyle’s Law is also known as ___
Mariotte’s Law
Laughing gas formula
Nitrous oxide (N2O)
Caustic soda formula
Sodium hydroxide (NaOH)
Baking soda formula
Sodium bicarbonate (NaHCO3)
the pressure that a gas will exert in a container assuming it was alone
partial pressure
Monazite formula
PO4SiO4
Nitroglycerin formula
C3H5N3O9
Cleveite
UO2
Chlorophyll formula
C55H72MgN4O5
DNA formula
C39H50O22N15P3
it denotes the relative amount of bonds H formed between the atoms of a molecule.
Empirical formula
it denotes the actual number of each atom in a molecule
molecular formula
[True or False]
Density usually decreases with increasing temperature
True
the amount of heat necessary to raise the temperature of 1 g of liquid water by 1°C.
calorie
The heart of the scientific method is the _____ by collecting facts.
testing of hypotheses and theories
For medical purposes and to measure potential radiation damage, the absorbed dose is measured in ____. Different particles damage body tissues differently; the ___ is a measure of relative damage caused by type of radiation.
rads, rem
_______ is the use of radionuclei for
diagnostic imaging and therapy.
Nuclear medicine
______ is the combining of two lighter nuclei to form a heavier nucleus. The energy released in this process is the energy of our Sun.
Nuclear fusion
_______ is the splitting of a heavier nucleus into two or more smaller nuclei.
Nuclear fission
What kind of emission does not result in transmutation?
Gamma emission
[True or False] Rates of nuclear reactions are not affected by temperature or catalysts.
True
[True or False] Nuclear reactions release so much energy that the mass does change.
True
[True or False] Elements typically do change in a nuclear reaction
True
Isotope used for cancer therapy
Cobalt-60
Isotope used for heart scanning and exercise stress tests
Thallium-201
Isotope used to measure the water content in the body
Tritium
Isotope used for kidney scanning
Mercury-197
Isotope used for medical imaging and eye tumor diagnosis
Phosphorus-32
Why is it accurate to assume that the carbon-14 to carbon-12 ratio in a living plant remains constant over the lifetime of the plant?
2 assumptions:
(1) C-14 is continually generated in the upper atmosphere by the production and decay of N-14
(2) C-14 is incorporated into carbon dioxide and other carbon compounds are then distributed worldwide as part of the carbon cycle.
Carbon-14 dating of the Shroud of Turin indicated that the plant from which the shroud was made was alive around AD 1350. To how many half-lives does this correspond?
a bit more than 10% of the half life of C-14
Half life of C-14
5730 years
One sievert is equal to ____ rem
100
[True or False] an isotope is UNSTABLE if it has equal number of protons and neutrons
False
The higher the neutron/proton ratio, the (lower,higher) is the half life of an isotope
Lower
An unstable nucleus exhibits ______
radioactivity
Protons and neutrons, the elementary particles that make up the nucleus, are called ______
Nucleons
A _______ is a nucleus with a particular composition, that is, with specific numbers of the two types of nucleons.
Nuclide
[True or False] Alpha particles are identical to helium-4 nuclei.
True
____ particles are high speed electrons while ____ are very high energy photons
Beta, gamma rays
The decaying, or reactant, nuclide is called the ______; the product nuclide is called the ______.
Parent, daughter
The technique of radiocarbon dating, for which the American chemist __________ won the Nobel Prize in chemistry in 1960, is based on measuring the amounts of 14C and 12C in materials of biological origin.
Willard F. Libby
nuclei of the stable hydrogen isotope deuterium, 2H
deuterons
The world’s most powerful accelerator is the ________ near Geneva, Switzerland
Large Hadron Collider (LHC)
The ______ invented by ______ in 1930, applies the principle of the linear accelerator but uses electromagnets to give the particle a spiral path to save space.
cyclotron, E. O. Lawrence
The _______ uses a synchronously increasing magnetic field to make the particle’s path circular rather than spiral.
synchrotron
[True or False] penetrating power is inversely related to the mass, charge, and energy of the emission
True
[True or False] Alpha particles are massive and highly charged, which means that they interact with matter most strongly of the three common emissions.
True
[True or False] an external gamma ray source is the most dangerous because the energy can ionize many layers of living tissue.
True
A tiny amount of a radioisotope mixed with a large amount of a stable isotope of the same element can act as a ______, a chemical “beacon” emitting radiation that signals the presence of the substance.
Tracer
the energy required to break 1 mol of nuclei into individual nucleons
Nuclear binding energy
[True or False] the greater the binding energy per nucleon, the more stable the nuclide is.
True
He pointed out that the lack of chemical reactivity of the noble gases (Group 8A) indicates a high degree of stability of their electron configuration
Gilbert N. Lewis
a measure of an atom’s attraction for the electrons it shares in a chemical bond with another atom.
Electronegativity
the most electronegative element
Fluorine
The most widely used scale of electronegativities was devised by ________ in the 1930s. On the scale, fluorine, the most electronegative element, is assigned an electronegativity of 4.0, and all other elements are assigned values relative to fluorine.
Linus Pauling
_____ measures the amount of energy necessary to remove an electron from an atom
Ionization energy
_______ measures how tightly an atom holds the electrons that it shares with another atom
Electronegativity
Who proposed the theory of resonance?
Linus Pauling
According to this theory, many molecules and ions are best described by writing two or more Lewis structures and considering the real molecule or ion to be a hybrid of these structures.
Theory of resonance
According to this model, the valence electrons of an atom may be involved in the formation of single, double, or triple bonds, or they may be unshared. Each combination creates a negatively charged region of electron density around the nucleus. Because like charges repel each other, the vari- ous regions of electron density around an atom spread out so that each is as far away as possible from the others.
valence-shell electron-pair repulsion (VSEPR) model.
The ______ states that elements of Groups 1A–7A tend to gain or lose electrons so as to achieve an outer shell containing eight valence electrons.
Octet rule
What are the three main inorganic components of one dry mixture currently used to create synthetic bone?
calcium dihydrogen phosphate, calcium phosphate, and calcium carbonate
What is the medical use of barium sulfate
to visualize the gastrointestinal tract by x-ray examination.
What is the main metal ion present in bone and tooth enamel?
Ca2+
If you read the labels of sun-blocking lotions, you will find that a common UV-blocking agent is a compound containing zinc. Name and write the formula of this zinc-containing compound.
Zinc Oxide
We are constantly warned about the dangers of “lead- based” paints. Name and write the formula for a lead- containing compound found in lead-based paints.
Lead(IV) oxide and lead(IV) carbonate
Iron forms Fe2+ and Fe3+ ions. Which ion is found in the over-the-counter preparations intended to treat “iron-poor blood”?
Fe2+
Teflon
Tetrafluoroethylene
[True or False] The amount of heat given off or absorbed is proportional to the amount of material.
True
Major component of natural gas
Methane
Major component of LPG or bottled gas
Propane
Which of the following polymers is the most suitable in creating the most effective bulletproof vest?
A. Polymethacrylate fiber
B. Polyamide fiber
C. Polycarbonate fiber
D. Polyethylene fiber
D. Polyethylene fiber
Used by Kevlar (bulletproof vest)
A. Polymethacrylate fiber
B. Polyamide fiber
C. Polycarbonate fiber
D. Polyethylene fiber
B. Polyamide fiber
Which of the following polymers is a common material of construction for radiation protection
A. Polymethacrylate fiber
B. Polyamide fiber
C. Polycarbonate fiber
D. Polyethylene fiber
A. Polymethacrylate fiber
Which of the following polymers used for bulletproof windows?
A. Polymethacrylate fiber
B. Polyamide fiber
C. Polycarbonate fiber
D. Polyethylene fiber
C. Polycarbonate fiber
Commonly used in identifying the molecular mass (actual MW) of a compound
Platinichloride Method
“Electron” was coined by _____
George Storey
He did the oil drop experiment and determined the charge of an electron
Robert Millikan
He proposed that energy like matter is discontinuous
Max Planck
According to ____, a system may possess an infinite amount of energy.
Classical Physics
According to this theory, a system may only possess a finite, discrete amount of energy
Quantum Theory
The cumulative energy that each particle of a system possesses
Internal Energy
Van der Waal’s Force is also known as
A. Dispersion force
B. London force
C. Instantaneous induced dipole interaction
D. All of the above
D. All of the above
Bonds between atoms
Intramolecular forces
Bond between molecules
Intermolecular forces
It occurs on the molecules on the surface of a liquid due to the unbalanced distribution of forces
Surface Tension
He introduced the concept of entropy
Rudolf Clausius
A thermodynamic property that measures the various ways in which a systems energy can be dstributed among its components
Entropy
Proponent of wave-particle duality
Albert Einstein
The process is _____ when the entropy of the universe is positive while the gibbs free energy of the system is negative
A) Spontaneous
B) Non spontaneous
C) Reversible, equilibrium
A) Spontaneous
The process is _____ when the entropy of the universe is negative while the gibbs free energy of the system is positive
A) Spontaneous
B) Non spontaneous
C) Reversible, equilibrium
B
The process is _____ when the entropy of the universe and the gibbs free energy of the system are zero
A) Spontaneous
B) Non spontaneous
C) Reversible, equilibrium
C
The process involves the addition of infinitesimal amounts of heat to a system that causes incremental changes in its properties
Reversible
Liquid to vapor phase transition involves ____ enthalpy and ____ entropy
A) positive, negative
B) negative, negative
C) positive, positive
D) negative, positive
C
It is a measure for the maximum available energy for non-PV work
Gibb’s Free Energy
[True or False] Colligative properties depend ONLY on the concentration of the solute
True
The amount of pressure necessary to impede the phenomena of osmosis
Osmotic pressure
A phenomena of solvent to flow through a semipermeable membrane to equalize the concentration on both sides
Osmosis
He discovered the noble gases
William Ramsey
Which of the ff is the third gas that William Ramsay isolated with Morris Travers
A) Argon
B) Neon
C) Krypton
D) Xenon
D) Xenon
The gas that William Ramsay discovered along with Lord Rayleigh
Argon
The gas that William Ramsay discovered along with Frederick Soddy
Radon “Radium Emanation”
Three gases that Ramsay and Travers discovered
Neon, Krypton, Xenon
A noble gas derived from an ire of uranium (cleveite)
Helium
How many carbon atoms are there in one molecule of “buckyball”?
A) 20
B)40
C)60
D)80
C60
Who discovered radioactivity?
Henri Becquerel
Marie Curie discovered these two elements
Polonium and Radium
Father of nuclear chemistry
Otto Hahn
Discovered nuclear fission
Otto Hahn
Discovered transmutation (the nuclei of an atom will undergo transformation when bombarded w/ a nuclear species
Ernest Rutherford
Who synthesized the first synthetic transmutated atom
Irene Joliot Curie
First transmutated atom
P-30
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 is the phosphor of a 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 cause the greatest damage to a material assuming that all of them can penetrate it equally?
A: 100 rad Gamma rays
B: 100 rad Beta Emission
C: 100 rad Neutron Emission
D: 100 rad Alpha Emission
D: 100 rad Alpha Emission
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 a Solar Eclipse
A: In the Water surrounding the core of a Nuclear Reactor
Across the three most notorious accidents regarding nuclear power plants: Three Mile Island, Chernobyl, and Fukushima, what is the most common cause for their failure that led to several environmental problems?
A: A leak in the fuel rods initiating an explosion
B: Bursting of reactor due to uncontrolled pressurized steam
C: Loss of proper cooling and/or moderator
D: Run-off chain reactions of the fissile material
C: Loss of proper cooling and/or moderator
The Bataan Nuclear Power Plant is planned to be retrofitted in hopes of using it for the first time. One point of concern is the material that would be used in the outer portions of the room housing the fuel rods. If the radiation coming from the fuel rods would be a strong beta emission, which material among the following should be utilized?
A: 1.00 cm of Aluminum
B: 7.50 m of Concrete
C: 8.0 mm of Lucite
D: 35.0 m of Lead
C: 8.0 mm of Lucite
Quantum number - distance of e- from nucleus
n (principal quantum number)
Quantum number - shape of the volume of space that the e- occupies
l azimuthal/angular momentum
Quantum number - orientation of orbital in space
ml magnetic
Quantum number - interaction with a magnetic field
ms spin
Same number of electrons / same number of electronic configuration
A) isoelectronic
B) isotone
C) isotope
D) isobar
A
Same number of neutrons
A) isoelectronic
B) isotone
C) isotope
D) isobar
B
Same number of protons but different mass number
A) isoelectronic
B) isotone
C) isotope
D) isobar
C
Same mass number
A) isoelectronic
B) isotone
C) isotope
D) isobar
D
the ___ principle means fill the orbitals from bottom to top.
Aufbau
_____ rule requires single occupancy before pairing.
Hund’s
No two electrons in a atom can have an identical set of four quantum numbers
Pauli’s Exclusion Principle
Who proposed Quantum Theory?
Max Planck
How many water molecules can
attach to methanol via hydrogen
bonding?
A: 2 B: 3 C: 4 D: 5
B: 3
What intermolecular forces does
CH3CHOHCH3 have?
A: Hydrogen Bonding only
B: London Forces and Hydrogen Bonding
C: Dipole-Dipole Forces and Hydrogen
Bonding
D: London Forces, Dipole-Dipole
Forces, and Hydrogen Bonding
D: London Forces, Dipole-Dipole
Forces, and Hydrogen Bonding
Which among the following
substances has the highest surface
tension?
A:CCl4
B:CH3OH
C:CH3CH2OCH2CH3
D:NOTA
B:CH3OH
Determine whether the following
statements are TRUE or FALSE.
(a.) The internal energy of a system
comprises that of the energy of every
single microscopic particle that makes
up that system
(b.) Heat and work can be conserved in
a system by distributing it evenly
amongst the systems constituents
(c.) delta U being equal to the
summation of heat and work is an
interpretation of the First Law of
Thermodynamics
(d.) delta H can be interpreted as the
heat transferred under constant volume
conditions.
A: False, False, True, True
B: True, True, True, True
C: False, True, True, False
D: True, False, True, False
D: True, False, True, False
Determine whether the following
statements are TRUE or FALSE:
(a.) Ludwig Boltzmann introduced the
concept of entropy and elucidated its
behavior in order to explain the
direction of spontaneous change
(b.) When the temperature of a system
is increased, the number of feasible
microstates decrease, effectively
leading to an increase in entropy
(c.) A process wherein two ideal gases
in separate bulbs, both at a pressure
of 1 bar, are connected and allowed to
expand into the total volume, exhibits
a positive change in entropy
A: True, False, True
B: False, False, True
C: True, True, False
D: False, True, False
B: False, False, True
Which among the following
relationships fully encapsulates the
idea of the Second Law of
Thermodynamics
A: delta S_system < 0
B: delta S_universe > delta S_system +
delta S_surrounding
C: delta S_universe > 0
D: delta S_system <deltaS_surrounding
C: delta S_universe > 0
For the combustion of liquid
acetylene in the presence of oxygen,
liquid water and carbon dioxide gas is
produced. Given this reaction, which
among the following statements is
TRUE?
A: Since delta S is positive, delta G
is more negative than delta H
B: Since delta S is negative, delta G
is more negative than delta H
C: Since delta S is positive, delta G
is less negative than delta H
D: Since delta S is negative, delta G
is less negative than delta H
D: Since delta S is negative, delta G
is less negative than delta H
Sherwood Roland and Mario Molina’s
work on stratospheric ozone depletion
garnered them the 1995 Nobel Prize in
Chemistry. Which among the following
species did they determine act as a
catalyst for the decomposition of
ozone?
A: Refrigerants B: CClF3
C: Nitrogen Oxides D: Chlorine Atoms
D: Chlorine Atoms
For a biochemical study involving
the tigers at Malabon Zoo, a fatty acid
was labeled with carbon-14. The sample
was then fed to the tigers and after a
few hours the tigers breath was
analyzed. In which among the following
compounds would you expect for the
radioactive material to be detected?
A: As Nitrogen B: As Carbon Dioxide
C: As Hydrogen D: As Water Vapor
B: As Carbon Dioxide
Raschig process is the production of ____
hydrazine
Determine the percent atom economy
of the Raschig Process.
A: 17.3%
B: 22.4%
C: 34.7%
D: 46.5%
A: 17.3%
give the balanced chemical equation of Raschig process
2NH3 + Cl2 + 2NaOH –> N2H4 + 2NaCl + H2O
Which among the following
radioactive nuclide is often bombarded
with the various isotopes of lead in
order to produce most of the new
superheavy elements?
A: Iodine-131 and Lawrencium-257
B: Chromium-51 and Gallium-67
C: Calcium-48 and Nickel-64
D: Selenium-75 and Krypton-81m
C: Calcium-48 and Nickel-64
who discovered superheavy elements from Plutonium to Lawrencium
Glenn T. Seaborg
who discovered I-131
Glenn T. Seaborg
Isotope to diagnose albinism
Cr-51
Isotope for whole body scan for tumors
Gallium-67
Buck and Axel
Olfactory receptors
Vitamin A
Retinol
Vitamin B12
Cobalamin
Number of double bonds in geraniol
A. 3 C. 0
B. 1 D. 2
D. 2
What is another name for lecithin?
A. Phosphatidylcholine C. Sodium benzoate
B. Xanthan gum D. Ascorbic acid
A. Phosphatidylcholine
What structural characteristics do citric acid and malic acid have in common?
A. They are heterocyclic compounds
B. Both has three moieties of carboxylic acid
C. They contain an alkene bridge
D. They are both hydroxy acids
D. They are both hydroxy acids
Define a salt in terms of acids and bases.
A. A salt is a compound that follows Le Chatelier principle in reactions with other
compounds.
B. All of these
C. A salt is a compound formed when the nucleus of a hydrogen atom enters a quantity
of water.
D. A salt is a compound (other than water) produced by the reaction of acid and a base.
D. A salt is a compound (other than water) produced by the reaction of acid and a base.
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
For a particular chemical reaction, ΔH˚ is positive and ΔS˚ is negative. Which of
the following statements about the spontaneity of the reaction under standard conditions
is TRUE?
A. The reaction will be spontaneous only if the magnitude of ΔH˚ is large enough to
cover the unfavorable entropy change.
B. The reaction will be spontaneous only if the magnitude of ΔS˚ is large enough to
overcome the unfavorable enthalpy change.
C. The reaction will be spontaneous regardless of the magnitudes of ΔH˚ and ΔS˚.
D. The reaction cannot be spontaneous.
D. The reaction cannot be spontaneous.
Radioactive solid nuclear wastes are disposed off by
A. high temperature incineration
B. pyrolysis
C. pathological incineration
D. underground burial in concrete containers
D. underground burial in concrete containers
Which forces are stronger, intramolecular covalent
bonds or intermolecular hydrogen bonds?
Intramolecular covalent bonds are stronger than
intermolecular hydrogen bonds.
Which types of solids have the highest melting
points? Which have the lowest melting points?
Ionic and network solids have the highest melting
points. Molecular solids have the lowest melting points.
What happens when
a person lowers the diaphragm in his or her chest
cavity?
When the diaphragm is lowered, the volume of the
chest cavity increases, lowering the pressure in the lungs
relative to the atmospheric pressure. Air at atmospheric
pressure then rushes into the lungs, beginning the breathing process.
In a sphygmomanometer
one listens to the first tapping sound as the constrictive pressure of the arm cuff is slowly released. What
is the significance of this tapping sound?
The first tapping sound one hears is the systolic pressure, which occurs when the sphygmomanometer pressure
matches the blood pressure when the ventricle contracts,
pushing blood into the arm.
If you fill a glass bottle
with water, cap it, and cool to 210°C, the bottle will
crack. Explain.
When water freezes, it expands (water is one of the few
substances that expands on freezing) and will crack the bottle when the ice expansion exceeds the volume of the bottle.
6.83 It is difficult to compress liquids and solids because
their molecules are already very close together and there is
very little empty space between them
Why do aerosol cans carry the warning “Do not
incinerate”?
Aerosol cans already contain gases under high pressure. Gay-Lussac’s law predicts that the pressure inside the
can will increase with increasing temperature, with the
potential of explosive rupture of the can, causing injury.
Why does the temperature of a liquid drop as a
result of evaporation?
The temperature of a liquid decreases during evaporation because the molecules with higher kinetic energy leave
the liquid, which decreases the average kinetic energy of
those molecules remaining in the liquid.
To a separatory funnel with two layers—the nonpolar diethyl ether and the polar water—is added a
small amount of solid. After shaking the separatory
funnel, in which layer will we find each of the following solids?
(a) NaCl
(b) Camphor, C10H16O
(c) KOH
(a) NaCl (an ionic solid) will dissolve in the polar
water layer.
(b) Camphor (a nonpolar molecule) will dissolve in the
nonpolar diethyl ether layer.
(c) KOH (an ionic solid) will dissolve in the polar water
layer.
Suppose that we have a stain on an oil painting that
we want to remove without damaging the painting.
The stain is not water-insoluble. Knowing the polarities of the following solvents, which one would we try
first and why?
(a) Benzene, C6H6
(b) Isopropyl (rubbing) alcohol, C3H7OH
(c) Hexane, C6H14
Isopropyl alcohol would be a good first choice. The oil
base in the paint is nonpolar. Both benzene and hexane are
nonpolar solvents and may dissolve the paint, destroying
the painting
The solubility of aspartic acid in water is 0.500 g in
100 mL at 25°C. If we dissolve 0.251 g of aspartic
acid in 50.0 mL of water at 50°C and let the solution
cool to 25°C without stirring, shaking, or otherwise
disturbing the solution, would the resulting solution
be a saturated, unsaturated, or supersaturated solution? Explain.
supersaturated
If a bottle of beer is allowed to stand for several
hours after being opened, it becomes “flat” (it loses
CO2). Explain.
According to Henry’s law, the solubility of a gas in
a liquid is directly proportional to the pressure. A closed
bottle of a carbonated beverage is under excess CO2 pressure. After the bottle is opened, the excess CO2 pressure
is released and the CO2 escapes from solution as bubbles
of gas.
Which of the following would produce the brightest
light in the conductance apparatus shown in Figure 7.10?
(a) 0.1 M KCl
(b) 0.1 M (NH4)3PO4
(c) 0.5 M sucrose
(b) 0.1 M (NH4)3PO
On the basis of Tables 7.1 and 7.2, classify the following systems as homogeneous, heterogeneous, or colloidal mixtures.
(a) Physiological saline solution
(b) Orange juice
(c) A cloud
(d) Wet sand
(e) Suds
(f ) Milk
(a) homogeneous (b) heterogeneous (c) colloidal
(d) heterogeneous (e) colloidal (f) colloidal
A solution of protein is transparent at room temperature. When it is cooled to10°C, it becomes turbid. What causes this change in appearance?
As the temperature of the solution decreases, the
protein molecules aggregate and form a colloidal mixture.
The turbid appearance is the result of the Tyndall effect.
What makes normal
rainwater slightly acidic?
Carbon dioxide (CO2) dissolves in rainwater to form
a dilute solution of carbonic acid (H2CO3), which is a
weak acid
What is nitrogen
narcosis?
Nitrogen dissolved in the blood can lead to a narcotic
effect referred to as “rapture of the deep,” which is similar
to alcohol-induced intoxication.
What is the chemical
formula for the main component of limestone and
marble?
calcium carbonate, CaCO3.
What is the minimum
pressure on sea water that will force water to flow
from the concentrated solution into the dilute
solution?
The minimum pressure required for reverse osmosis
in the desalinization of sea water exceeds 100 atm (the
osmotic pressure of sea water).
What is the minimum
pressure on sea water that will force water to flow
from the concentrated solution into the dilute
solution?
The minimum pressure required for reverse osmosis
in the desalinization of sea water exceeds 100 atm (the
osmotic pressure of sea water).
Synovial fluid that exists in joints is a colloidal solution of hyaluronic acid (Section 20.6A) in water.
When a biochemist wants to isolate hyaluronic acid
from synovial fluid, he or she adds ethanol, C2H6O,
to bring the solution to 65% ethanol. The hyaluronic
acid precipitates upon standing. What makes the
hyaluronic acid solution unstable and causes it to
precipitate?
The ethanol molecules
If a certain reaction takes 16 h to go to completion at
10°C, what temperature should we run it if we want
it to go to completion in 1 h?
50°C would predict completion of the reaction in 1 h
If you were running a reaction and wanted it to go
faster, what three things might you try to accomplish
this goal?
You might (a) increase the temperature, (b) increase
the concentration of reactants, or (c) add a catalyst.
Explain how a catalyst increases the rate of a reaction
A catalyst increases the rate of a reaction by providing
an alternative reaction pathway with lower activation
energy.
A painkiller—for example, Tylenol—can be purchased in two forms, each
containing the same amount of drug. One form is a
solid coated pill, and the other is a capsule that contains tiny beads and has the same coat. Which medication will act faster? Explain
The capsule with the tiny beads will act faster than
the solid coated-pill form. The small bead size increases the
drug’s surface area, allowing the drug to react faster and
deliver its therapeutic effects more quickly.
Which weak base is used
as a flame retardant in plastics?
Mg(OH)2 is a weak base used in flame-retardant
plastics.
With respect to corneal
burns, are strong acids or strong bases more
dangerous?
Strong bases are more harmful to the cornea because
the healing of the wounds can deposit nontransparent scar
tissue that impairs vision
What causes (a) respiratory acidosis and (b) metabolic acidosis?
(a) Respiratory acidosis is caused by hypoventilation,
which occurs due to a variety of breathing difficulties,
such as a windpipe obstruction, asthma, or pneumonia.
(b) Metabolic acidosis is caused by starvation or heavy
exercise
Suppose you have a phosphate buffer of pH 7.21.
If you add more solid NaH2PO4 to this buffer, would
you expect the pH of the buffer to increase, decrease,
or remain unchanged? Explain
DECREASE
As the concentration of H2PO4 increases, the log becomes negative, lowering the pH and becoming more acidic.
What is the ratio of HPO /H2PO in a phosphate
buffer of pH 7.9 (the pH of human pancreatic fluid)?
4.9 : 1 or 5:1
Name the major physiologically active substances that
comes from:
bark of the willow tree
the pituitary gland,
the sap of the poppy,
belladenna plant.
Salicin,
beta-endomorphin,
opium,
atropine
What is the buckyball?
A. An epoxy resin
B. C60H+++
C. A fullerene
D. Sodium benzoate
C. A fullerene
A solution of cation gives a crimson red
flame. This flame test is a confirmatory test
for:
a. Sr2+ c. Mn2+
b. K+ d. Ca2+
a. Sr2+
What is the color of nickel chloride?
a. white c. red
b. blue d. yellow
d. yellow
Substances whose solutions change color
due to changes in pH
Indicator
It is an organic reaction that converts an
alcohol into an alkyl chlorine using
triphenylphosphine and carbon tetrachloride.
Appel Reaction
Which of the following indicators is used in
EDTA titration?
A. Solochrome C. Eriochrome Black T
B. Calmagite D. All of these
D. All of these
Taurine, a Beta amino acid belongs to the
acidic group of:
A. –SO2OH C. –COOH
B. –COONH3 D. –C=OH
A. –SO2OH
In a standard chemical reaction, rate is governed by the relationship
rate=pze-E/RT, where p and z refer to the probability that reacting
molecules make a favorable encounter. To increase the probability of
reaction, enzymes are employed. Based on the above equation, if E is the
activation energy, which is more favorable and why? A lower or hgher E?
A. Lower E so that more molecules possess sufficient energy to react
B. Higher E so that a better nucleophile and electrophile are catalyzed
C. Lower E so that a proton can be donated or stolen for the reactants
leading to better catalysis
D. Higher E so the bonds of the reactants will be strained and provide
more power transition state condition
C. Lower E so that a proton can be donated or stolen for the reactants
leading to better catalysis
The coexistence curve where the plot of pressure versus temperature
along which the two phases coexist was shown by ClausiusClapeyron. What did Clausius postulate?
A. The Clapeyron equation was simplified by assuming that the vapor
obeys the ideal gas law and by neglecting the molar volume of the
liquid VL in comparison with the molar volume of the gas VG
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 molar volume of the
liquid VL in comparison with the molar volume of the gas VG
What is the theory in two or three dimensional collision to be
applied when playing billiard balls and in order to sink the target
ball in the corner pocket?
A. The center of the mass theory where the center of the mass
of the system moves as all the mass in the system were
concentrated at that point, and one of them is initially at rest, and
they were in perpendicular direction of the collision
B. Proton-proton elastic collision
C. The component of momentum an isolated system in each of
the directions (x, y, z) are conserved independently
D. Where two equal masses undergo a glancing elastic collision
D. Where two equal masses undergo a glancing elastic collision
When travelling at NLEX at 80mph, a stopped car in
front causes you to suddenly skid to stop. What
happened to the kinetic energy of the moving car?
A. Some of it were converted to internal energy and
some transferred to the road and surroundings
B. It was transferred to the internal energy of the
road
C. All of it transferred to the road and surroundings
D. All of it are still in the car
C. All of it transferred to the road and surroundings
Are reversible processes frictionless? Why?
A. Because the processes are driven by forces
which imbalance is differential in magnitude
B. Because when reversed, retraces its forward
path and restores the initial state of the system
and surroundings
C. None of these
D. Because only infinitesimal changes occur
B. Because when reversed, retraces its forward
path and restores the initial state of the system
and surroundings
What is the Nujol Mull in organic chemical reactions?
A. It is a mass spectrum technique and is obtained by grinding up a
solid which is mixed with mineral oil to form a suspension for IR
spectroscopy
B. It is the name of a type of paraffin oil from India and most often
used in gas chromatography to enhance the mass transfer
properties of compounds
C. It is a process applied for inorganic compounds to determine the
effervescence of the compound under study
D. It is suspension in mineral oil which is placed in between HgCl, AgI
and KCl or stainless steel plates to obtain a good spectrum
A. It is a mass spectrum technique and is obtained by grinding up a
solid which is mixed with mineral oil to form a suspension for IR
spectroscopy
