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Physical Chemistry
12 Rate of reaction is defined as the
Rate of change of conc. of product only
Rate of change of conc. of reactant only
Rate of change of concentration Of either reactant or product per unit time
None of the above
13 The rate of chemical reaction
Increases as the reaction proceeds
Decreases as the reaction proceeds
Both (a) and (b)
Remains constant as reaction proceeds
14 The factor that affects the rate of reaction is
Temperature of the reactants
Nature and concentration of the reactants
Catalyst
All of these
15 In general, the rate of a reaction can be increased by all the
factors except
Increasing the activation energy
Increasing the temperature
Increasing the concentration of reactants
Using a catalyst
Rate of change of conc. of product only
Rate of change of conc. of reactant only
Rate of change of concentration Of either reactant or product per unit time
None of the above
13 The rate of chemical reaction
Increases as the reaction proceeds
Decreases as the reaction proceeds
Both (a) and (b)
Remains constant as reaction proceeds
14 The factor that affects the rate of reaction is
Temperature of the reactants
Nature and concentration of the reactants
Catalyst
All of these
15 In general, the rate of a reaction can be increased by all the
factors except
Increasing the activation energy
Increasing the temperature
Increasing the concentration of reactants
Using a catalyst
Physical Chemistry
8 Rusting of iron Is an example of________ reaction
Slow
Fast
Moderate
explosive
9 In the reaction: $2B \rightarrow Product$; the rate equation is: Rate
= k[B]. If the concentration of ‘B’ is doubled, the rate of reaction
will increase by a multiple of
Four
Two
Three
None of these
10 Powdered marble reacts more rapidly with HCl than the chips of marble
because:
Surface area of powdered marble is more that of chips of marble and
hence there is more collisions between the molecules of reactants
Number of molecules increases.
Energy of activation decreases
Marble chips will not react with HCl
11 The term — dx/dt in the rate expression refers to the
instantaneous rate of the reaction
Average rate of the reaction
increase in concentration of the reactants
Change in concentration of the reactants with time
Slow
Fast
Moderate
explosive
9 In the reaction: $2B \rightarrow Product$; the rate equation is: Rate
= k[B]. If the concentration of ‘B’ is doubled, the rate of reaction
will increase by a multiple of
Four
Two
Three
None of these
10 Powdered marble reacts more rapidly with HCl than the chips of marble
because:
Surface area of powdered marble is more that of chips of marble and
hence there is more collisions between the molecules of reactants
Number of molecules increases.
Energy of activation decreases
Marble chips will not react with HCl
11 The term — dx/dt in the rate expression refers to the
instantaneous rate of the reaction
Average rate of the reaction
increase in concentration of the reactants
Change in concentration of the reactants with time
Physical Chemistry
4 The minimum additional energy, above the average internal energy,
which the reacting molecules must possess so that their collision result
in a reaction is known as
Kinetic energy
Threshold energy
Activation energy
Thermodynamic energy
5 The reactions with the high value of energy of activation are
Fast
Slow
Moderate
Not feasible
6 The reactions catalyzed by sunlight are called ____________ reactions
Endothermic
Exothermic
Sun-lighted
photochemical
7 In a reaction: $2A \rightarrow B + 2C$, which of the statement is true?
Rate of formation of B = Rate of disappearance of A
Rate of formation of C= Rate of formation of B
Rate of disappearance of A = Rate of formation of C
Rate of disappearance of A = Rate of formation of B
which the reacting molecules must possess so that their collision result
in a reaction is known as
Kinetic energy
Threshold energy
Activation energy
Thermodynamic energy
5 The reactions with the high value of energy of activation are
Fast
Slow
Moderate
Not feasible
6 The reactions catalyzed by sunlight are called ____________ reactions
Endothermic
Exothermic
Sun-lighted
photochemical
7 In a reaction: $2A \rightarrow B + 2C$, which of the statement is true?
Rate of formation of B = Rate of disappearance of A
Rate of formation of C= Rate of formation of B
Rate of disappearance of A = Rate of formation of C
Rate of disappearance of A = Rate of formation of B
Physical Chemistry
1 Which of the following statements about the kinetics of the reaction
$H_2(g) + Br_2(g) \rightarrow 2HBr(g)$ is definitely true?
The reaction is first order with respect to bromine, Br2.
The reaction is second order overall.
The presence of hydrogen bromide, HBr, inhibits the rate of the reaction
It is not possible to determine anything about the kinetics of the
reaction from the stoichiometry.
2 Milk sours more rapidly in summer than in winter because
in summer, the temperature Is high due to which effective collisions
increase and hence the rate of reaction becomes fast
in winter, number of molecules per unit volume increases and hence the
rate of reaction becomes fast
in summer, the energy of activation decreases and hence the of reaction
becomes fast
none of the above
3 For a reaction: $2H_2 + 2NO \rightarrow 2H_2O + N_2$ the rate law is
$R = K [H_2][NO]^2$ The Order of the reaction is?
0
3
2
1
$H_2(g) + Br_2(g) \rightarrow 2HBr(g)$ is definitely true?
The reaction is first order with respect to bromine, Br2.
The reaction is second order overall.
The presence of hydrogen bromide, HBr, inhibits the rate of the reaction
It is not possible to determine anything about the kinetics of the
reaction from the stoichiometry.
2 Milk sours more rapidly in summer than in winter because
in summer, the temperature Is high due to which effective collisions
increase and hence the rate of reaction becomes fast
in winter, number of molecules per unit volume increases and hence the
rate of reaction becomes fast
in summer, the energy of activation decreases and hence the of reaction
becomes fast
none of the above
3 For a reaction: $2H_2 + 2NO \rightarrow 2H_2O + N_2$ the rate law is
$R = K [H_2][NO]^2$ The Order of the reaction is?
0
3
2
1
Physical Chemistry
16 How long would a constant current of 18.0 amperes be required to flow
in order for 9000. coulombs of charge to pass through a cell
200 s
500 s
0.002 s
50 s
17 The pH of a neutral solution is
5
6
7
8
18 The pH of a solution is 4.6; what is its pOH?
2.4
9.4
11.6
4.6
19 Which of the followings is not a Bronsted acid?
HCl
$AlCl_3$
$HNO_3$
$H_2SO_4$
20 The conjugate base of HCl is
HOCl
$H^{+}$
$Cl^{-}$
$ OH^{-}$
in order for 9000. coulombs of charge to pass through a cell
200 s
500 s
0.002 s
50 s
17 The pH of a neutral solution is
5
6
7
8
18 The pH of a solution is 4.6; what is its pOH?
2.4
9.4
11.6
4.6
19 Which of the followings is not a Bronsted acid?
HCl
$AlCl_3$
$HNO_3$
$H_2SO_4$
20 The conjugate base of HCl is
HOCl
$H^{+}$
$Cl^{-}$
$ OH^{-}$
Physical Chemistry
12 Which of the following mixtures produces a buffer solution?
0.300 M NaOH + 0.100 M HCl (50 mL each)
0.300 M $KNO_3$ + 0.100 M NaCl (50 mL each)
0.300 M $NH_4Cl$ + 0.100 M HCl (50 mL each)
0.400 M $CH_3COOH$ + 0.100 M $CH_3COONa$ (50 mL each)
13 Buffering is:
due to LeChatelier's Principle
is a process that is done by a solution made up of a weak acid and its salt
influenced by the common ion effect
all of these
14 What’s the concentration of Ag+ ion in a saturated silver chloride
solution? $K_{sp}$ = 1.56 x$10^{-10}$.
0.0000125 M
4.90 M
0.000339 M
none of these
15 How many coulombs of charge pass through a cell if 2.40 amperes of
current are passed through the cell for 85.0 minutes?
204 C
0.133 C
12200 C
2120 C
0.300 M NaOH + 0.100 M HCl (50 mL each)
0.300 M $KNO_3$ + 0.100 M NaCl (50 mL each)
0.300 M $NH_4Cl$ + 0.100 M HCl (50 mL each)
0.400 M $CH_3COOH$ + 0.100 M $CH_3COONa$ (50 mL each)
13 Buffering is:
due to LeChatelier's Principle
is a process that is done by a solution made up of a weak acid and its salt
influenced by the common ion effect
all of these
14 What’s the concentration of Ag+ ion in a saturated silver chloride
solution? $K_{sp}$ = 1.56 x$10^{-10}$.
0.0000125 M
4.90 M
0.000339 M
none of these
15 How many coulombs of charge pass through a cell if 2.40 amperes of
current are passed through the cell for 85.0 minutes?
204 C
0.133 C
12200 C
2120 C
Physical Chemistry
8 The magnitude of $K_{w}$ indicates that __________.
water autoionizes very slowly
water autoionizes very quickly
water autoionizes only to a very small extent
the autoionization of water is exothermic
9 Which of these is incorrect about the pH of a solution?
It is a measure of the acidity of the solution
The higher the pH, the more acidic the solution is
pH = -log$[H^{+}]$
an alkali has a higher pH value than an acid
10 The common-ion effect
promotes condensation
promotes evaporation.
increases solubility
reduces ionization.
11 Consider the equilibrium of AgCl(s) in water. What is the effect of
adding KCl?
The KCl has no effect
The reaction goes to the right
The reaction goes to the left
Silver chloride solubility increases
water autoionizes very slowly
water autoionizes very quickly
water autoionizes only to a very small extent
the autoionization of water is exothermic
9 Which of these is incorrect about the pH of a solution?
It is a measure of the acidity of the solution
The higher the pH, the more acidic the solution is
pH = -log$[H^{+}]$
an alkali has a higher pH value than an acid
10 The common-ion effect
promotes condensation
promotes evaporation.
increases solubility
reduces ionization.
11 Consider the equilibrium of AgCl(s) in water. What is the effect of
adding KCl?
The KCl has no effect
The reaction goes to the right
The reaction goes to the left
Silver chloride solubility increases
Physical Chemistry
4 For the following reaction, which of the following is a conjugate
acid-base pair? $H_{2}PO^{4-} (aq) + NH_{3} (aq) \rightarrow
HPO_{4}^{2-} (aq) + NH_{4}^{+} (aq)$
$H_2PO_4^-$ and $NH_3$
HPO42- and NH4+
$H_2PO_4^-$ and $HPO_4^{2-}$
None of the above
5 What is the conjugate base of $HCO_{3}^{-}$?
$CO_{3}^{2-}$
$H_{2}CO_{3}$
$HCO_{3}^{+}$
OH^{-}
6 A Brønsted-Lowry acid is defined as a substance that ______ .
acts as a proton acceptor
acts as a proton donor
increases [OH– ] when dissolved in water
decreases [H3O+] when dissolved in water
7 A substance that is capable of acting as both an acid and as a base is
_____.
Amphoteric
Diprotic
Binary acid-base
conjugated
acid-base pair? $H_{2}PO^{4-} (aq) + NH_{3} (aq) \rightarrow
HPO_{4}^{2-} (aq) + NH_{4}^{+} (aq)$
$H_2PO_4^-$ and $NH_3$
HPO42- and NH4+
$H_2PO_4^-$ and $HPO_4^{2-}$
None of the above
5 What is the conjugate base of $HCO_{3}^{-}$?
$CO_{3}^{2-}$
$H_{2}CO_{3}$
$HCO_{3}^{+}$
OH^{-}
6 A Brønsted-Lowry acid is defined as a substance that ______ .
acts as a proton acceptor
acts as a proton donor
increases [OH– ] when dissolved in water
decreases [H3O+] when dissolved in water
7 A substance that is capable of acting as both an acid and as a base is
_____.
Amphoteric
Diprotic
Binary acid-base
conjugated
Physical Chemistry
1 For the following reaction, which of the following is a conjugate
acid-base pair? $HC_2O_4^-(aq)$ + $H_2O(l)$ $\rightarrow$ $H_3O^+$(aq) +
$C_2O_4^{2-}$(aq)
$HC_{2}O_{4}^{-}$ and $H_{2}O$
$H_{2}O$ and $C_{2}O{4}^{2-}$
$HC_2O_4^-$ and $H_3O^+$
$HC_{2}O_{4}^{-}$ and $C_{2}O_{4}^{2-}$
2 In the following reaction, which is a Brønsted-Lowry base?
$HC_{2}O_{4}^{-}(aq) + H_{2}O(l) \rightarrow H_{3}O^{+}(aq) +
C_{2}O_{4}^{2-}(aq)$
$HC_{2}O_{4}^{-}$
$H_{2}O$
$H_{3}O^+$
None of these
3 A Brønsted-Lowry base is defined as a substance that
acts as a proton donor.
increases [H+] when placed in water.
acts as a proton acceptor.
decreases [H+] when placed in water.
acid-base pair? $HC_2O_4^-(aq)$ + $H_2O(l)$ $\rightarrow$ $H_3O^+$(aq) +
$C_2O_4^{2-}$(aq)
$HC_{2}O_{4}^{-}$ and $H_{2}O$
$H_{2}O$ and $C_{2}O{4}^{2-}$
$HC_2O_4^-$ and $H_3O^+$
$HC_{2}O_{4}^{-}$ and $C_{2}O_{4}^{2-}$
2 In the following reaction, which is a Brønsted-Lowry base?
$HC_{2}O_{4}^{-}(aq) + H_{2}O(l) \rightarrow H_{3}O^{+}(aq) +
C_{2}O_{4}^{2-}(aq)$
$HC_{2}O_{4}^{-}$
$H_{2}O$
$H_{3}O^+$
None of these
3 A Brønsted-Lowry base is defined as a substance that
acts as a proton donor.
increases [H+] when placed in water.
acts as a proton acceptor.
decreases [H+] when placed in water.
Physical Chemistry
16 Predict the signs of $\DeltaH$ and $\DeltaS$ for the evaporation of
water at $35^ºC$.
$\DeltaH$ > 0 and $\Deltas$ > 0
$\DeltaH$ > 0 and $\Deltas$ < 0
$\DeltaH$ < 0 and $\Deltas$ > 0
$\DeltaH$ < 0 and $\Deltas$ < 0
17 Every type of chemical bond contains a certain amount of energy. The
total bond energy, which is essentially equivalent to the total
potential energy of the system, is a quantity known as:
entropy.
kinetic energy.
enthalpy.
free energy.
18 A reaction with a negative value of ΔG is said to be
Spontaneous
Non-spontaneous
At equilibrium
Reversible
19 If a process is exothermic and not spontaneous, then what must be true?
$\DeltaS$ > 0
$\DeltaS$ < 0
$\DeltaH$ > 0
$\DeltaG$ = 0
20 In a reaction in which the rate of the reverse reaction is equal to
the rate of the forward reaction, a state of ____________ is attained.
total entropy
thermodynamics
dynamic equilibrium
product reversibility
water at $35^ºC$.
$\DeltaH$ > 0 and $\Deltas$ > 0
$\DeltaH$ > 0 and $\Deltas$ < 0
$\DeltaH$ < 0 and $\Deltas$ > 0
$\DeltaH$ < 0 and $\Deltas$ < 0
17 Every type of chemical bond contains a certain amount of energy. The
total bond energy, which is essentially equivalent to the total
potential energy of the system, is a quantity known as:
entropy.
kinetic energy.
enthalpy.
free energy.
18 A reaction with a negative value of ΔG is said to be
Spontaneous
Non-spontaneous
At equilibrium
Reversible
19 If a process is exothermic and not spontaneous, then what must be true?
$\DeltaS$ > 0
$\DeltaS$ < 0
$\DeltaH$ > 0
$\DeltaG$ = 0
20 In a reaction in which the rate of the reverse reaction is equal to
the rate of the forward reaction, a state of ____________ is attained.
total entropy
thermodynamics
dynamic equilibrium
product reversibility
