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General Chemistry Multiple Choice Questions with Answers and Explanations: Molarity, Acids, Bases, Equilibrium.

The minimum combined kinetic energy reactant particles must possess in order for their collision to result in a reaction is called the
Answer
A.
collision energy.
B.
orientation energy.
C.
activation energy.
D.
dissociation energy.

Question 2

The defining expression for the molarity concentration unit is
Answer
A.
moles of solute/liters of solution.
B.
grams of solute/liters of solution.
C.
moles of solute/liters of solvent.
D.
grams of solute/liters of solvent.

Question 3

For a system at chemical equilibrium,
Answer
A.
reactant and product concentrations are equal.
B.
reactant and product concentrations are zero.
C.
forward and reverse reaction rates are zero.
D.
forward and reverse reaction rates are equal.

Question 4

What is the volume, in liters, occupied by 2.85 moles of N2 gas at 0.958 atm pressure and a temperature of 39Ã?ºC?
Answer
A.
9.5 L
B.
76.2 L
C.
69.9 L
D.
L

Question 5

Indicate what the missing words are in the following statement of Charles' law: At constant pressure, the volume of a gas sample is _______ proportional to its _______ temperature.
Answer
A.
inversely; Kelvin
B.
directly; Celsius
C.
directly; Kelvin
D.
inversely; Celsius

Question 6

A colloidal dispersion differs from a true solution in that colloidal particles
Answer
A.
are large enough to be seen with the naked eye.
B.
are large enough to be seen with a microscope.
C.
are large enough to scatter light.
D.
tend to settle at an appreciable rate.

Question 7

The term nuclear energy is most closely associated with which one of the following processes?
Answer
A.
nuclear fission
B.
radioactive decay
C.
bombardment reactions
D.
nuclear fusion

Question 8

A volatile liquid would
Answer
A.
have weak attractive forces between molecules.
B.
have a low vapor pressure at room temperature.
C.
no correct response
D.
evaporate ââ?¬Å"slowlyââ?¬Â? at room temperature.
E.
more than one correct response

Question 9

In a solution, the solvent is
Answer
A.
always water.
B.
the substance being dissolved.
C.
always a liquid.
D.
the substance present in the greatest amount.

Question 10

Liquids will boil at lower temperatures at higher elevations because
Answer
A.
the intermolecular attractions are weaker.
B.
the vapor pressure at which boiling occurs is lower.
C.
it is harder to transfer heat to the liquid.
D.
atmospheric pressure increases.

Question 11

Which of the following does NOT describe an acidic solution?
Answer
A.
The [H3O+] is greater than the [OHââ?¬"]
B.
The [OHââ?¬"] is greater than 1.0 x 10ââ?¬"7
C.
The [OHââ?¬"] is 6.0 x10ââ?¬"10
D.
The pH is less than 7.0

Question 12

A solution is made by dissolving 0.35 mole of LiF in enough water to give a final volume of 190.0 mL. What is the molarity of the solution?
Answer
A.
1.9 M
B.
0.07 M
C.
0.9 M
D.
1.8 M

Question 13

Le Chatelier's principle states that
Answer
A.
if a chemical equilibrium is disturbed, the system will try and reestablish equilibrium.
B.
only reactions in which a catalyst is present can reach chemical equilibrium.
C.
only exothermic reactions can reach chemical equilibrium.
D.
if a chemical equilibrium is disturbed, the temperature of the system will always decrease.

Question 14

Which of the following equations represents an acid-base neutralization reaction?
Answer
A.
no correct response
B.
H2SO4 + Zn ââ? ' ZnSO4 + H2
C.
more than one correct response
D.
HNO3 + KOH ââ? ' KNO3 + H2O
E.
Ba(OH)2 + Na2SO4 ââ? ' BaSO4 + 2NaOH

Question 15

Which of the following types of radiation is composed of particles with a charge and mass identical to that of an electron?
Answer
A.
gamma radiation
B.
X-rays
C.
beta particles
D.
alpha particles

Question 16

Which of the following solutions has a molarity of 1.0?
Answer
A.
3.0 moles of solute in 1.5 L of solution
B.
2.0 moles of solute in 500.0 mL of solution
C.
more than one correct response
D.
no correct response
E.
0.050 mole of solute in 25.0 mL of solution

Question 17

Which of the following is produced in the first step of the dissociation of the acid H3PO4?
Answer
A.
PO43ââ?¬"
B.
H3PO3
C.
H2PO4ââ?¬"
D.
HPO42ââ?¬"

Question 18

Which of the following statements concerning evaporation is incorrect?
Answer
A.
Molecules with energies considerably above average are those which escape from the liquid.
B.
Evaporation causes the liquid temperature to decrease.
C.
Increasing the surface area of the liquid decreases the rate of evaporation.
D.
Increasing the temperature of the liquid increases the rate of evaporation.

Question 19

Which of the following solutions would always contain 10.0 g of solute per 40.0 g of solvent?
Answer
A.
20.0% (m/m) solution
B.
25.0% (v/v) solution
C.
no correct response
D.
25.0% (m/v) solution
E.
more than one correct response

Question 20

Compared to pure water, a 1 M sugar-water solution will have a
Answer
A.
lower vapor pressure, lower boiling point and lower freezing point.
B.
lower vapor pressure, higher boiling point and lower freezing point.
C.
higher vapor pressure, higher boiling point and higher freezing point.
D.
lower vapor pressure, lower boiling point and higher freezing point.

Question 21

When the vapor pressure of a liquid equals atmospheric pressure, the temperature of the liquid equals
Answer
A.
the normal boiling point of the liquid.
B.
more than one correct response
C.
the boiling point of the liquid.
D.
no correct response
E.
100Ã?º C if the liquid is at sea level.

Question 22

In terms of subatomic particles, the composition of an alpha particle is
Answer
A.
one neutron and two protons.
B.
one neutron and three protons.
C.
three neutrons and a proton.
D.
two neutrons and two protons.

Question 23

The half-life of a radionuclide is
Answer
A.
twice the time it takes for one quarter of a given quantity of the radionuclide to decay.
B.
no correct response
C.
the time it takes for half of a given quantity of the radionuclide to decay.
D.
half the time it takes for all of a given quantity of the radionuclide to decay.
E.
more than one correct response

Question 24

Which of the following is not a conjugate acid/base pair?
Answer
A.
NH4+/NH3
B.
CO2/CO3ââ?¬"
C.
H3PO4/H2PO4ââ?¬"
D.
OHââ?¬"/O2ââ?¬"

Question 25

Which of the following pairings of pH and hydronium ion concentration is correct?
Answer
A.
pH = 2.0; [H3O+] = 1 Ã?â?" 102
B.
pH = 9.0; [H3O+] = 9 Ã?â?" 10ââ?¬"9
C.
more than one correct response
D.
pH = 7.0; [H3O+] = 1 Ã?â?" 10ââ?¬"7
E.
no correct response

Solution Preview

Question 1
The minimum combined kinetic energy reactant particles must possess in order for their collision to result in a reaction is called the
Answer
A. collision energy.
B. orientation energy.
C. activation energy.
D. dissociation energy.

*ACTIVATION ENERGY - refers to the amount of energy required by certain chemicals for them to have a reaction and thereby produce the products. It serves as an energy barrier that must be overcome by the reactants for the reaction to start.
______________________

Question 2

The defining expression for the molarity concentration unit is
Answer
A. moles of solute/liters of solution.
B. grams of solute/liters of solution.
C. moles of solute/liters of solvent.
D. grams of solute/liters of solvent.

*MOLARITY = MOLES of solute per Liter of SOLUTION [This is the most commonly used concentration unit, which is also equal to mass / (molar mass* volume)
______________________

Question 3

For a system at chemical equilibrium,
Answer
A. reactant and product concentrations are equal.
B. reactant and product concentrations are zero.
C. forward and reverse reaction rates are zero.
D. forward and reverse reaction rates are equal.

*CHEMICAL EQUILIBRIUM is said to be achieved by a system when the FORWARD AND THE REVERSE REACTION RATES have become EQUAL. The reaction then is said to be in a state of balance.
________________________

Question 4

What is the volume, in liters, occupied by 2.85 moles of N2 gas at 0.958 atm pressure and a temperature of 39Ã?ºC?
Answer
A. 9.5 L
B. 76.2 L
C. 69.9 L
D. L

*Ideal Gas Equation: PV = nRT
V = nRT / P = (2.85 moles*0.08205 L atm/mole K *(39+273 K)) / 0.958 atm = 76.2 L
Ideal gas equations are useful when the problem is asking for any of the following values: Volume, Temperature, Pressure or moles of a given gas at a specific condition. Note that the temperature must always be expressed in Kelvin.
________________________

Question 5

Indicate what the missing words are in the following statement of Charles' law: At constant pressure, the volume of a gas sample is _______ proportional to its _______ temperature.
Answer
A. inversely; Kelvin
B. directly; Celsius
C. directly; Kelvin
D. inversely; Celsius

*Charles' Law states that the volume of a certain gaseous substance is DIRECTLY PROPORTIONAL to its absolute (Kelvin) temperature at constant pressure. The equation for this Law is: V1/T1 = V2/T2
____________________________

Question 6

A colloidal dispersion differs from a true solution in that colloidal particles
Answer
A. are large enough to be seen with the naked eye.
B. are large enough to be seen with a microscope.
C. are large enough to scatter light.
D. tend to settle at an appreciable rate.

*Colloids have larger particles than solution. Colloids are the only type of mixtures that can exhibit Tyndall Effect (scattering of light). Colloidal particles DON'T SETTLE UPON STANDING.
_____________________________

Question 7

The term nuclear energy is most closely associated with which one of the following processes?
Answer
A. nuclear fission
B. radioactive decay
C. bombardment reactions
D. nuclear fusion

*Nuclear energy usually ...

Solution Summary

This solution consists of 25 general chemistry questions on the following topics:concentration, kinetics, equilibrium, colligative properties, radioactivity, subatomic particles, intermolecular forces, activation energy, Le Chatelier's principle among others. Each question has an explanation on how to arrive at the correct answer. The formula and solution for the mathematical problems are also given in detail.

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