Mark (1) for True and (2) for False questions
(F) The relative humidity in a hot summer day in Florida
is 95%. Therefore, the partial pressure of water vapor in that day is 760
mm Hg (or torr) ´ 0.95 = 722 mm Hg (or
torr). What is the saturated water vapor pressure
that day and what is the 95% partial pressure of that pressure?
(T) Solutions can be in the form of either gases, liquids,
or solids.
(F) A solution is formed by dissolving a solute in a
solvent to form a heterogeneous solution.
(T) A soap molecule has both hydrophilic and hydrophobic
parts.
(F) Soap is completely soluble in water.
It forms micelles in water.
(T) Protein molecules are still hydrated even in
their crystal state.
(F) The water in the common chemical CuSO4·
5H2O cannot be removed at all. Heat
it up!
(F) Salts are comprised of anions and cations, therefore
all salts are water soluble. Find a few examples
in the book that are not soluble!
(F) Grease cannot be dissolve by solvent at all.
How about gasoline?
(F) All substances become more soluble at higher temperature.
How about gases?
(T) The "acid factor" in any sour food is actually
the proton. Is it H+ or H3O+?
(F) Molarity is defined as the number of moles
of a solute dissolved in 1 L of solvent.
Is osmolarity defined as the number of osmoles of
a solute dissolved in 1 L of solvent?
(F) When 100 mL of 0.90% NaCl solution is added
into 100 mL of the same solution, the concentration
becomes half.
(F) pH 7 is considered neutral therefore there
is no H+ in solution. Then,
what is it?
(T) The mass percent concentration of a solution can
be defined as the mass of solute in g in 100 g of the solution.
(T) Metal alloy can be considered a solution.
(F) A wine of 13.3%(v/v)
contains 13.3 g ethanol in every 100 mL of the wine.
(T) The unit ppm can be defined as the amount of solute
in mg in every 1 kg of solution.
(T) The concentration of 2.0 ppm lead(II) aqueous solution
can be converted to 9.7 m M.
(T) 1 ppm = 1000 ppb
(F) An amount of 6.0 L solvent is needed to add to 100
mL of a 0.090 M solution to dilute the solution into 0.0015 M. Think
about the FINAL volume!
(T) Vapor pressure of a solvent is lowered when solute
is dissolved in the solvent.
(F) Salt water should exhibit a lower
boiling temperature than pure water under the same conditions.
(T) Water boils at less than 100 deg-C on high mountains.
(F) When salt is spread on icy road, the ice melts because
salt water has higher melting temperature than pure water.
(F) You can dissolve BaCl2 and K2SO4
in water to obtain clear solution. Are they
soluble?
(T) You can also dissolve NaCl and K2SO4
in water to obtain clear solution.
(T) Insoluble compounds can form by mixing clear
KCl and AgNO3 solutions. What is
the precipitate?
(T) A "concentration" equivalent of molarity is
found in osmosis, which takes into consideration of the number of particles
in the solution.
(T) 1 M NaCl and 1 M KCl generate the same osmotic pressure.
(F) 1 M NaCl and 1 M glucose also generate the same osmotic
pressure.
(F) The osmotic pressure generated by 1 M NaCl
is double than that by 1M CaCl2. Why
not?
(T) A hypotonic solution has a lower concentration
than the internal solution of a cell, thus there is a net flow of water
into the cell.
(F) Any water soluble compound that contains H
can release that H to form H3O+ in water to become
an acid. Find an example or two that are not!
(T) CO2 becomes as an acid when dissolved
in water. What is this acid called?
(F) Water is always produced when a base is neutralized
with an acid. What was the example we gave
in the lecture?
(F) The stomach fluid is very acidic, and has a
very high pH. What is the pH?
(F) The proton concentration at pH 4 is double than that
at pH 2. Don't guess, do the calculation and
find out!
(F) There is no proton in an aqueous solution at pH 14
because it is the upper limit of the pH scale. Then,
how much?
(T) The acidity of a solution can be determined by the
OH– concentration of the solution. Are
we sure? Why?
(F) The OH– ion determines the basicity of
a solution. Therefore, in a very acidic solution, like the sulfuric acid
solution in your car battery, there is no OH– ion. What
is the concentration of OH– ion in a sulfuric acid solution
of pH 1?
(F) A compound which can dissociate OH– is
a base, thus CH3OH is a base. Can
CH3OH generate OH–? or H+?
(F) Two factors can affect solubility, which are molar
mass and volume. Find out in your book!
(T) The product [H3O+][OH–]
in water solution is always a constant. What
is the value?
(T) Pure water can dissociate to generate H+,
thus is an acid.
(T) The conjugate acid of ammonia is NH4+,
which is formed by reaction of ammonia with water.
(F) An aqueous solution of [OH–] = 2.00 ´
10–10 M gives pH = 9.70. Find out
[H+] first, of course!
(F) An aqueous solution of pH 5.3 has [H+]
= 5.0 m M. Then,
what is it?
(T) A compound which can serve as a buffer can
neutralize both acids and bases.
(F) Both protons in H2CO3
can also completely dissociate when dissolved in water. What
is bicarbonate?
(F) Weak bases produce weak conjugate acids, and weak
acids produce weak bases. Read the concept
about conjugate acids/bases!
Part II. Multiple Choice Questions
(5) The activation energy of a reaction
(1) is not
affected by a catalyst.
(2) is always
higher in an endothermic reaction than in an exothermic reaction.
(3) is always
the same for a forward and a reverse reaction.
(4) is changed
by changing the temperature.
(5) All the
above are not correct!
(3) If the equilibrium constant for the equilibrium A
h 2B is 9, the concentration of B is ___ times than that of A at equilibrium.
(1) 2
(2) 3 (3) 5 (4) 7
(5) 9
(3) A container with a volume 22.4 L contains 1.0
mol nitrogen and 2.0 mol hydrogen at 0 °C. Which of the following statement
is true? (The molar volume of gases is 22.4 L.)
(1) The pressure
in the container is 1.0 atm.
(2) The partial
pressures of N2 and H2 are the same.
(3) The pressure
in the container is 2280 mm Hg.
(4) The partial
pressure of N2 is 1.0/3.0 atm.
(3) An inflated balloon at 20.0 °C has a volume
2.0 L. What is the new volume when it is heated to 40.0 °C?
(1) 4.0 L
(2) 1.0 L (3) 2.1 L (4)
1.9 L
(1) How much methane is in 2.24 L at 15.0 atm and
42 °C? The gas constant is 0.082 atm L/mol K.
(1) 20.8 g
(2) 41.6 g (3) 9.76 mol
(4) 0.1 mol
(4) In the reaction A + B ®
2C + 10 cal, the equilibrium concentrations are found to be [A] = [B] =
0.5 M, and [C] = 0.1 M. What is the equilibrium constant of this reaction?
(1) 25
(2) 2.5 (3) 0.4 (4) 0.04
(1) Given the equilibrium reaction,
131 kJ + C(s) + H2O(g) h CO(g) + H2(g); s: solid
and g: gas
Increase in
pressure, the equilibrium is moved to
(1) left
(2) right (3) No effect!
(4) The boiling temperature of methane is not extreme
low near the absolute zero. This is due to the interaction between methane
molecules via
(1) hydrogen
bond (2) dipole-dipole interaction
(3) non-polar interaction (4) London force
(5) covalent bond
(4) The chapter 7 cover story describes the use
of a chemical for the treatment of edema to prevent brain injury. What
is that chemical?
(1) menthol
(2) glucose (3) methanol
(4) mannitol (5) physiological saline
(3) The compound BaSO4 is used in the
hospitals
(1) as a pesticide.
(2) as an antacid. (3) for X-ray image of the digestive
system. (4) for MRI image enhancement.
(5) as an anti-diarrhea agent.
(4) There are _____(how many) compounds in the followings
that are considered not soluble in water.
BaSO4, NaBr, CaF2, Ca3(PO4)2,
FeS
(1) 1
(2) 2 (3) 3 (4) 4
(5) 5 Which ones?
(3) There are _____(how many) compounds in the followings
that are considered soluble in water.
NaBr, Hg2Cl2, KCl, sodium acetate, CaF2
(1) 1
(2) 2 (3) 3 (4) 4
(5) 5
(5) In 75.0 g of 7.20% glucose solution, there is
an amount of ____ glucose in the solution.
(1) 7.20 g
(2) 7.20 mol (3) 75.0 g
(4) 5.40 mol (5) 5.40 g
(4) In 200 g 5.50% glucose solution, there is an
amount of ____ water in the solution.
(1) 11.0 g
(2) 11.0 mol (3) 89.0 g
(4) 189 g (5) 200 g
(2) Physiologic saline solution is 0.90% NaCl. The
red blood cells in a 5.0% NaCl solution
(1) does not
change (2) shrink (3) burst
open (4) cannot determine.
(2) An amount of 0.005 g Pb(II) in 2.0 L water is
___ ppm.
(1) 0.25 ppm
(2) 2.5 ppm (3) 25 ppm
(4) 0.005/207 ppm
(3) What is the mass-mass percent concentration
of a 5.0% (mass/volume) NaCl solution?
(1) 5.0%
(2) 5.2% (3) 4.8% (4) Cannot
do the conversion!
(2) What is the molarity (M) of a 5.0% (m/v) NaCl
solutin?
(1) 0.085
M (2) 0.85 M (3) 8.5 M
(4) 5.0 M
(3) Which one of the following compounds is not
a Bronsted-Lowry acid?
(1) HCl
(2) H2O (3) CH4
(4) CH3COOH (5) H2CO3
(2) Which of the following substances dissolve most
readily in the nonpolar solvent hexane C6H14?
(1) MgCl2
(2) vegetable oil (3) HCl
(4) vinegar (5) baking soda
(4) Suppose that you would like to prepare 200 mL
of a 0.50 M NaBr solution using a 2.0 M NaBr stock solution. How many milliliters
of the stock solution should you use?
(1) 25 mL
(2) 100 mL (3) 150 mL (4)
50 mL (5) 200 mL
(2) How many grams of glucose must be dissolved
in 1.0 L of water to make a solution that has a glucose concentration of
1 ppm?
(1) 1.0 g
(2) 10–3 g (3) 103 g
(4) 102 g (5) 0.1 g
(3) A certain wine is 14.0% ethanol (m/v). What
is the mass of ethanol, C2H5OH, in 1 L of the wine?
(1) 6.4 g
(2) 71.4 g (3) 140 g (4)
64.0 g (5) 46.0 g
(4) How many moles of potassium iodide (KI) do you
need to make 0.200 M KI solution?
(1) 0.200
(2) 0.100 (3) 165.9 (4)
Cannot determine!
(2) You add 3 L of juice to 1 L of a 60% liquor,
what is the ethanol concentration in the final cocktail?
(1) 20%
(2) 15% (3) 10% (4) 5%
(5) Cannot determine!
(1) The lower the pH, the _____ acidic the solution.
(1) more
(2) less (3) Cannot determine the acidity without
giving the pH value!
(2) The ionization constant of an acid A is smaller
than an acid B, when same number of moles of the acids are taken for the
preparation of two different solutions, the solution of A is ____ acidic
than the solution of B.
(1) more
(2) less (3) Cannot determine without knowing the
values of the constants!
(5) Which one of the following compounds is not
a BrÆ nsted-Lowry base?
(1) NaOH
(2) NH3 (3) H2O
(4) Ca(OH)2 (5) All of the above are BrÆnsted-Lowry
base
(3) The Kw value of water is
(1) pH 7
(2) 14 (3) 10–14 (4)
10–7 (5) cannot determine.
(3) The pH of a H2SO4 solution with a concentration of
0.005 M is
(1) 10–2
(2) 1 (3) 2 (4) 5
(5) cannot determine.
(2) Which solution is the most acidic? Which
one can DISSOCIATE more H+?
(1) 1M HCl
(2) 1M H2SO4 (3) 1 M CH3COOH
(4) 1 M H3PO4
(3) Which solution is the most basic? (What are
the values of [OH–] for the solutions?)
(1) 1.0 M
sugar solution (2) 0.001 M NaOH solution
(3) pH 12 solution (4) solution with [H+]=10–10
M (5) pure water
(4) What is the pH value of a solution of [OH–]
= 4.0 × 10–11 M?
(1) 11
(2) 10.4 (3) 4 (4) 3.6
(5) cannot determine
(4) The pH of blood is 7.4. What is the [H3O+]
of blood?
(1) 7.4 M
(2) 7.4 mM (3) 2.5 ´
107 M (4) 4.0
´ 10–8 M
(3) What is the pH of a 3 M HCl (hydrochloric acid)?
(1) 3
(2) 0.48 (3) –0.48 (4)
Cannot determine!
(2) What is the pH value of a solution of [OH–]
= 4.0 × 10–11 M?
(1) 4.0
(2) 3.6 (3) 10.4 (4) Cannot
determine!
(3) . What is the pH of a 5 M NaOH solution?
(1) 5
(2) 0.70 (3) –0.70 (4)
Cannot determine!
(4) How many moles of NaOH is
required to neutralize x moles of H2SO4?
(1) 1
(2) 2 (3) x (4) 2x
(5) x/2
(3) How many moles of Ca(OH)2 is
required to neutralize x moles of H2SO4?
(1) 1
(2) 2 (3) x (4) 2x
(5) x/2
(2) Which acid contains the largest
number of protons per molecule, acetic acid, phosphoric acid, hydrochloric
acid, sulfuric acid, or carbonic acid?
(1) acetic
acid (2) phosphoric acid
(3) hydrochloric acid (4) sulfuric acid
(5) carbonic acid
(4) Solubility is defined
as the amount of substance dissolves in a fixed amount of solvent at ##
to produce a __________ solution
(1) concentrated
(2) dilute (3) clear (4)
saturated
(3) How much NaCl is needed
to make 500 mL physiologic saline, 0.90% NaCl (m/v)
(1) 0.90 g
(2) 0.9 mol (3) 4.5 g (4)
0.45 g (5) 0.045 g
(2) The "pure" ethanol you use
is 95% ethanol. What is the real percentage of the final ethanol solution
when 75 mL of the pure ethanol is diluted to a volume of 250 ml with water?
(1) 30%
(2) 28.5% (3) 33% (4) 3.3%
(5) A phosphoric acid of 1 N is
equivalent to ___ M.
(1) 1
(2) 2 (3) 3 (4) 1/2
(5) 1/3
(5) When 100 mL 0.50 M H2SO4
is completely neutralized with 0.25 M NaOH, how much of this NaOH solution
is needed?
(1) 50 mL
(2) 100 mL (3) 200 mL (4)
300 mL (5) 400 mL
(4) The pH of 5.0 ´
10–3 M H2SO4 is
(1) –2.3
(2) 2.3 (3) –2.0 (4) 2.0
(5) 0.70
(4) What is the pH of a 2.3 ´
10–4 M Ca(OH)2 aqueous solution?
(1) 3.6
(2) 3.3 (3) 10.4 (4) 10.7
(3) Knowing pKa = pH
– log([proton acceptor]/[proton donor]), the pH of an aqueous solution
consisting of 0.0080 M acetic acid and 0.0040 sodium acetate is _____.
The Ka value of acetic acid is 1.74 ´
10–5 M.
(1) 4.63
(2) 5.06 (3) 4.46 (4) 0.30
(5) –0.30
(3) Which one is a weak acid?
(1) HCl
(2) H2SO4 (3) H2CO3
(4) HNO3