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Cumulative Exam — Cumulative exam Answers

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A student requires 2.00 L of 0.100 M NH4NO3 from a 1.75 M NH4NO3 stock solution. What is the correct way to get the solution?Use .

Question illustration
A
Measure 114 mL of the 1.75 M solution, and dilute it to 1.00 L.
B
Measure 114 mL of the 1.75 M solution, and dilute it to 2.00 L.
C
Measure 8.75 mL of the 1.75 M solution, and dilute it to 2.00 L.
D
Measure 8.75 mL of the 0.100 M solution, and dilute it to 2.00 L.
2
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Which reactions are spontaneous?i. C2H5OH(l) + 3O2(g) 2CO2(g) + 3H2O(l), G = –36.7 kJii. 2C6H6(l) + 15O2(g) 12CO2(g) + 6H2O(l), G = –6,405 kJiii. CaCO3(s) CaO(s) + CO2(g), G = 13.0 kJiv. Ni(s) + Cl2(g) NiCl2(s), G = 1,130.28 kJ

Question illustration
A
i and ii
B
iii and iv
C
i and iii
D
ii and iv
3

Water is dissolved into n-butanol (a polar liquid). Which is the second step at the molecular level as water dissolves into n-butanol?

A
n-Butanol mixes with water.
B
Water molecules are carried into n-butanol.
C
n-Butanol molecules surround water molecules.
D
n-Butanol molecules are attracted to the surface of the water molecules.
4

Which is the first step in the dissolving process?

A
The solute becomes like the solvent.
B
The solute molecules are carried into the solution.
C
The solvent molecules surround the solute particles.
D
The solvent molecules are attracted to particles at the surface of the solute.
5

If the pressure of a gas is 2.000 × 104 kPa, what is its pressure in atm?

A
26.32 atm
B
197.4 atm
C
1.013 ´ 106 atm
D
2.026 ´ 106 atm
6

Consider the half reactions below for a chemical reaction.What is the overall equation for this chemical reaction?

Question illustration
A
Upper M g (s) plus 2 upper H superscript plus (a q) right arrow upper M g superscript 2 plus (a q) plus upper H subscript 2 (g).
Option A
B
Upper M g (s) plus 2 upper H superscript plus (a q) right arrow upper M g superscript 2 plus (a q) plus 2 e superscript minus.
Option B
C
Upper M g superscript 2 plus (a q) plus upper H subscript 2 (g) right arrow upper M g (s) plus 2 upper H superscript plus (a q).
Option C
D
Upper M g (s) plus 2 upper H right arrow upper M g (a q) plus upper H subscript 2 (g).
Option D
7

The reaction of a Lewis acid with a Lewis base would most likely be accompanied by an increase in which item?

A
covalent bonds
B
hydronium ions
C
electron pairs
D
hydroxide ions
8

Which answer choice represents a balanced alpha emission nuclear equation?

A
Superscript 52 subscript 26 upper F e right arrow superscript 52 subscript 25 upper M n plus superscript o subscript plus 1 e.
Option A
B
Superscript 235 subscript 92 upper U right arrow superscript 239 subscript 94 upper P u s plus superscript 4 subscript 2 upper H e.
Option B
C
Superscript 189 subscript 83 upper Bi right arrow superscript 185 subscript 81 upper T l plus superscript 4 subscript 2 H e.
Option C
D
Superscript 14 subscript 6 upper C right arrow superscript 14 subscript 7 upper N plus superscript 0 subscript negative 1 e.
Option D
9

The following half-reaction method is used to balance oxidation-reduction equations.(1) Determine which atoms change oxidation state from reactant to product in the reaction.(2) Identify and write half reactions (oxidation and reduction).(3) Return to the original chemical equation to balance it.(a) Insert the coefficients from the half reactions first.(b) Inspect the number of each atom on each side for all elements.Which important step is missing from this procedure?

A
Check other reactions similar to this one.
B
Name the elements that are involved in the reaction.
C
Make sure the reduction half reaction is identified first.
D
Balance the half reactions based on the number of electrons.
10

A miner develops cancer of the esophagus. Ten years before, he had been exposed to radiation when he worked for a year in a mine. He had also smoked cigarettes for a number of years, but had quit five years ago. Which statement best describes the miner’s condition?

A
Tests can determine whether the cancer was caused by exposure at the mine or by compounds in cigarette smoke so that a treatment can be determined.
B
Cancer caused by exposure at the mine would have appeared while he was at the mine, so smoking is the more likely cause.
C
The cancer is likely the result of natural exposure to radiation in the environment and not related to either the mine or smoking.
D
It is unlikely that a specific cause can be determined, but the treatment would likely be the same in either case.
11

Which is an example of ionization?

A
C + O2 CO2
Option A
B
H2CO3 H2O + CO2
Option B
C
SO2 + H2O HSO3– + H+
Option C
D
Mg(OH)2 Mg2+ + 2OH–
Option D
12

A chemical reaction has an increase in entropy and a decrease in enthalpy. What is known about the spontaneity of the reaction?

A
spontaneous at high temperatures, nonspontaneous at low temperatures
B
nonspontaneous at high and low temperatures
C
spontaneous at low temperatures, nonspontaneous at high temperatures
D
spontaneous at high and low temperatures
13

A chemistry journal requires that all new research papers be peer reviewed by other scientists before they are published. This allows which of the following?

A
The reviewers can determine the experiment’s feasibility.
B
The reviewers can determine the experiment’s validity.
C
The reviewers can include their own findings with the research.
D
The reviewers can determine if they will help fund the research.
14

Which is a characteristic of nuclear fission?

A
releases nonradioactive waste only
B
involves the collision of two nuclei
C
releases small amounts of energy compared to fossil fuels
D
involves the splitting of an atom into two or more fragments
15

Pure water at 25°C

A
ionizes in the presence of acid to form an equilibrium in which
Option A
B
ionizes in the presence of acid to form an equilibrium in which
Option B
C
self-ionizes to form an equilibrium in which
Option C
D
self-ionizes to form an equilibrium in which
Option D
16

A solar panel combines multiple photovoltaic cells. Which type of energy is used to power a solar panel?

A
kinetic energy
B
thermal energy
C
electromagnetic energy
D
gravitational potential energy
17

A radioactive nuclide that is used for geological dating has an atomic number of 19 and mass number 40. Which is the symbol of this nuclide?

A
Superscript 19 subscript 21 upper K.
Option A
B
Superscript 21 subscript 19 upper K.
Option B
C
Superscript 40 subscript 19 upper K.
Option C
D
Superscript 19 subscript 40 upper K.
Option D
18

Ca(OH)2 is added to a large beaker of water. How is the solution different from the original water?

A
The solution turns blue litmus to red.
B
The solution turns phenolphthalein pink.
C
The solution has more hydrogen ions.
D
The solution has fewer hydroxide ions.
19

Which reaction takes place in a nuclear fission reactor?

A
Superscript 13 subscript 6 upper C plus superscript 1 subscript 1 upper H right arrow superscript 14 subscript 7 upper N.
Option A
B
Superscript 239 subscript 94 upper P u plus superscript 4 subscript 2 upper H e right arrow superscript 242 subscript 96 upper C m.
Option B
C
Superscript 59 subscript 27 upper C o plus superscript 4 subscript 2 upper H e right arrow superscript 60 subscript 27 upper C o plus superscript 1 subscript 0 n.
Option C
D
Superscript 235 subscript 90 upper U plus superscript 1 subscript 0 n right arrow superscript 94 subscript 36 upper K r plus superscript 139 subscript 56 upper B a plus 3 superscript 1 subscript 0 n.
Option D
20

Which value is most likely to be the pH of a salt solution that is formed by the reaction of a strong acid and a weak base?

A
2.0
B
7.0
C
8.0
D
10.0

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