Physical Science Review

Multiple Choice

Identify the letter of the choice that best completes the statement or answers the question.

____ 1. Which statement about the atomic nucleus is correct?

a.	The nucleus is made of protons and neutrons and has a negative charge.
b.	The nucleus is made of protons and neutrons and has a positive charge.
c.	The nucleus is made of electrons and has a positive charge.
d.	The nucleus is made of electrons and has a negative charge.

____ 2. Atoms of elements that are in the same group have the same number of

a.	protons.	c.	valence electrons.
b.	neutrons.	d.	protons and neutrons.

____ 3. A lithium ion is much less reactive than a lithium atom because it

a.	is much more massive.
b.	has a full outermost energy level.
c.	has a negative electric charge.
d.	is in a different group in the periodic table.

____ 4. Oxygen’s atomic number is 8. This means that an oxygen atom has

a.	eight neutrons in its nucleus.	c.	eight protons in its nucleus.
b.	a total of eight protons and neutrons.	d.	a total of eight neutrons and electrons.

____ 5. An atom’s mass number equals the number of

a.	protons plus the number of electrons.	c.	protons.
b.	protons plus the number of neutrons.	d.	neutrons.

____ 6. Which statement about the alkali metals is correct?

a.	They are located in the left-most column of the periodic table.
b.	They are extremely nonreactive.
c.	They are usually gases.
d.	They form negative ions with a 1- charge.

____ 7. Which of the following elements is an alkali metal?

a.	Calcium	c.	mercury
b.	Magnesium	d.	sodium

____ 8. Alkali metals are extremely reactive because they

a.	have very small atomic masses.
b.	are not solids at room temperature.
c.	have one valence electron that is easily removed to form a positive ion.
d.	have two valence electrons that form compounds with calcium and magnesium.

____ 9. Which statement about noble gases is correct?

a.	They form compounds with very bright colors.
b.	They exist as single atoms rather than as molecules.
c.	They are highly reactive with both metals and nonmetals.
d.	They are extremely rare in nature.

____ 10. Group 18 noble gases are inert because

a.	they readily form positive ions.
b.	they can have either a positive or a negative charge.
c.	their outermost energy level is missing one electron.
d.	their outermost energy level is full.

____ 11. Atoms have no electric charge because they

a.	have an equal number of charged and noncharged particles.
b.	have neutrons in their nuclei.
c.	have an equal number of electrons and protons.
d.	have an equal number of neutrons and protons.

____ 12. According to Bohr’s model of the atom, electrons behave like

a.	planets orbiting the sun.	c.	light energy in a vacuum.
b.	waves on a vibrating string.	d.	planets rotating on their axes.

____ 13. The order of elements in the periodic table is based on

a.	the number of protons in the nucleus.	c.	the number of neutrons in the nucleus.
b.	the electric charge of the nucleus.	d.	atomic mass.

____ 14. Ionization refers to the process of

a.	changing from one period to another.	c.	turning lithium into fluorine.
b.	losing or gaining protons.	d.	losing or gaining electrons.

____ 15. Carbon and other nonmetals are found in which area of the periodic table?

a.	on the left-most side
b.	on the right side
c.	in the middle column of the periodic table
d.	in the bottom rows

____ 16. Valence electrons determine an atom’s

a.	mass.	c.	electric charge.
b.	chemical properties.	d.	period.

____ 17. The sub-orbital with highest energy is:

a.	s	c.	d
b.	p	d.	f

____ 18. If the atomic mass of carbon is 12 amu, 1 mole of pure carbon will have a mass of

a.	6 g.	c.	12 g.
b.	6 mol.	d.	12 mol.

____ 19. Avogadro’s constant is defined as the number of particles in

a.	one mole of a pure substance.	c.	one gram of a pure substance.
b.	one liter of a pure substance.	d.	one kilogram of a pure substance.

____ 20. Molar mass is defined as

a.	the number of particles in 1 mole of a substance.
b.	the SI base unit that describes the amount of a substance.
c.	the amount of a substance necessary to have a positive charge.
d.	the mass in grams of 1 mole of a substance.

____ 21. The forces that hold different atoms or ions together are

a.	electric currents.	c.	physical bonds.
b.	chemical bonds.	d.	nuclear forces.

____ 22. Each molecule of table sugar, C₁₂H₂₂O₁₁, contains

a.	0 atoms of carbon.	c.	6 atoms of carbon.
b.	1 atom of carbon.	d.	12 atoms of carbon.

____ 23. Which compound is formed from a tight network of oppositely charged ions?

a.	sugar, C₁₂H₂₂O₁₁	c.	water, H₂O
b.	quartz, SiO₂	d.	salt, NaCl

____ 24. In which substance do the molecules have the strongest attractions to one another?

a.	sugar, a solid	c.	sulfuric acid, a liquid
b.	hydrogen, a gas	d.	water, a liquid

____ 25. Gases take up a lot of space because

a.	they have weak chemical bonds.
b.	their molecules have very little attraction for one another.
c.	they contain very few atoms.
d.	they have a small molar mass.

____ 26. Often atoms join so that each atom will have

a.	an even number of electrons.
b.	an outermost energy level that is full of electrons.
c.	an equal number of protons and electrons.
d.	more electrons than either protons or neutrons.

____ 27. An ionic bond is a bond that forms between

a.	ions with opposite charges.
b.	atoms with neutral charges.
c.	one atom’s nucleus and another atom’s electrons.
d.	the electrons of two different atoms.

____ 28. Covalent bonds are formed between

a.	ions.	c.	nonmetal atoms.
b.	metal atoms.	d.	compounds.

____ 29. In which type of bond do atoms share electrons?

a.	covalent bonds	c.	ionic bonds
b.	metallic bonds	d.	polyatomic bonds

____ 30. The name dinitrogen tetroxide tells you that this compound contains

a.	two nitrogen atoms and two oxygen atoms.
b.	four nitrogen atoms and two oxygen atoms.
c.	two nitrogen atoms and four oxygen atoms.
d.	four nitrogen atoms and four oxygen atoms.

____ 31. Fe₂O₃ is named iron (III) oxide because it contains

a.	three oxygen atoms.	c.	three iron atoms.
b.	Fe³⁺ ions.	d.	O³⁺ ions.

____ 32. When copper combines with oxygen to form copper (II) oxide, the charge of the copper ion is

a.	Cu¹⁺.	c.	Cu³⁺.
b.	Cu²⁺.	d.	Cu⁴⁺.

____ 33. When nickel combines with fluorine to form nickel (III) fluoride, the charge of the nickel ion is

a.	Ni¹⁺.	c.	Ni³⁺.
b.	Ni²⁺.	d.	Ni⁴⁺.

____ 34. The name for the compound with the formula CuBr₂ would be written as

a.	copper(II) bromide.	c.	copper bromine.
b.	copper(I) bromide.	d.	copper(III) bromide.

____ 35. A carbon atom can bond to four other atoms because it has

a.	four different cations.	c.	two inner energy levels.
b.	four valence electrons.	d.	no protons in its nucleus.

____ 36. A change in the color of a solution is a sign that

a.	a chemical change is taking place.	c.	oxygen is present.
b.	a physical change has just occurred.	d.	organic chemicals are present.

____ 37. A substance that undergoes a change in a chemical reaction is

a.	a product.	c.	a reactant.
b.	a chemical.	d.	an enzyme.

____ 38. What happens in a chemical reaction?

a.	Atoms are destroyed.	c.	Molecules are created.
b.	Atoms are created.	d.	Atoms are rearranged.

____ 39. In an exothermic reaction, energy is transferred from

a.	the reactants to the surroundings.	c.	one reactant to another.
b.	the surroundings to the reactants.	d.	the container to the chemicals.

____ 40. A synthesis reaction is a reaction between at least two compounds in which

a.	one breaks down into at least two products.
b.	a compound is decomposed by an electric current.
c.	a compound burns in the presence of oxygen.
d.	a new, more complex compound is formed.

____ 41. Which of the following is an example of a decomposition reaction?

a.	photosynthesis
b.	digestion
c.	polymerization
d.	exchange of ions between two compounds

____ 42. When iron reacts with oxygen to form rust, each iron atom

a.	loses three ions.	c.	gains three ions.
b.	loses three electrons.	d.	gains three electrons.

____ 43. A chemical equation is balanced by changing or adding

a.	chemical symbols.	c.	coefficients.
b.	subscripts.	d.	reactants.

____ 44. A balanced chemical equation shows the proportions of reactants and products necessary for

a.	the reaction to occur.	c.	energy use to be minimized.
b.	mass to be conserved.	d.	electrolysis to occur.

____ 45. In the reaction 2H₂O ® 2H₂ + O₂, if you start with 2 mol of water, how many moles

of hydrogen gas are produced?

a.	1 mol	c.	3 mol
b.	2 mol	d.	4 mol

____ 46. In the reaction H₂S + 2O₂ ® H₂SO₄, the law of definite proportions predicts that for

every mole of H₂S you will need how many moles of O₂?

a.	1 mol	c.	3 mol
b.	2 mol	d.	4 mol

____ 47. In a balanced chemical reaction, the total mass of the products always equals the

a.	molar mass of the reactants.	c.	total mass of the reactants.
b.	atomic mass of the reactants.	d.	proportional masses of the reactants.

____ 48. All of the following factors may speed up a chemical reaction except

a.	smaller surface area.	c.	higher temperature.
b.	higher pressure.	d.	presence of a catalyst.

____ 49. An enzyme is a special kind of catalyst that works to

a.	speed up a specific biochemical reaction.
b.	break down chemical elements.
c.	slow down a chemical reaction.
d.	maintain the correct temperature for a reaction.

____ 50. When a chemical reaction and its reverse are occurring at the same time and at the same rate, the reaction has achieved

a.	displacement.	c.	imbalance.
b.	equilibrium.	d.	decomposition.

____ 51. Which of the following is an example of a heterogeneous mixture?

a.	salt water	c.	sugar solution
b.	vinegar	d.	mayonnaise

____ 52. A heterogeneous mixture is one that is not

a.	uniform throughout.	c.	made of two or more liquids.
b.	easily mixed together.	d.	edible by humans.

____ 53. Which of the following is a homogeneous mixture?

a.	salad dressing	c.	rubbing alcohol
b.	gelatin	d.	orange juice with pulp

____ 54. A mixture that separates into different layers when you stop stirring it is

a.	a colloid.	c.	a solution.
b.	a suspension.	d.	an emulsion.

____ 55. Which statement about solutions is incorrect?

a.	Liquids that mix to form a single layer are said to be miscible.
b.	Solutions can be made of liquids and solids, liquids and liquids, or gases and liquids.
c.	In a solution, the solvent is dissolved into the solute.
d.	Solutions will not separate under normal circumstances.

____ 56. You can usually separate out a suspension by

a.	pouring off the liquid.
b.	freezing the suspension.
c.	distilling the entire suspension.
d.	using a paper filter to catch the particles.

____ 57. Loose sugar dissolves much faster than a sugar cube because loose sugar has

a.	a greater surface area.	c.	a higher temperature.
b.	less kinetic energy.	d.	a greater surface tension.

____ 58. You can make a solute dissolve more quickly in a solvent by

a.	adding more solute.	c.	heating the solvent.
b.	adding ice.	d.	removing some solvent.

____ 59. All of the following will make it easier to dissolve a solute in a solvent except

a.	heating the solvent.
b.	stirring the solution.
c.	increasing the surface area of the solute.
d.	adding a larger amount of solute.

____ 60. Water can dissolve charged particles because

a.	it is an ionic compound.	c.	it is solid at a temperature of 0°C.
b.	its atoms have partial charges.	d.	its molecular weight is extremely low.

____ 61. Water is referred to as the universal solvent because

a.	it is found throughout the universe.
b.	all known substances dissolve in water.
c.	many different substances dissolve in water.
d.	it covers more than half of Earth’s surface.

____ 62. An unsaturated solution is one that

a.	can dissolve more solute at the current conditions.
b.	will precipitate out all its dissolved solute.
c.	can dissolve more solute only if heated.
d.	can dissolve more solute only if the pressure is increased.

____ 63. What happens when a supersaturated solution cools down?

a.	The solution starts to freeze at room temperature.
b.	The solution will accept even more solute.
c.	The solute will rise to the top of the solution.
d.	The solute will precipitate out of the solution.

____ 64. A bottle of soda fizzes when opened because the dissolved gas

a.	is insoluble in the soda.	c.	saturates the solution.
b.	reacts with the air.	d.	comes out of solution.

____ 65. You mix a powdered drink mix with water. The result is an example of a(n)

a.	suspension.	c.	colloid.
b.	solution.	d.	heterogeneous mixture.

____ 66. Because silver chloride, AgCl, is almost completely insoluble in water, the forces

between the ions in a crystal of AgCl must be

a.	nonpolar.	c.	extremely strong.
b.	partially covalent.	d.	weaker than those in a water molecule.

____ 67. An example of a nonpolar molecule is

a.	water.	c.	olive oil.
b.	vinegar.	d.	table salt.

____ 68. Some types of peanut butter settle into two layers, a solid layer and a liquid layer. These peanut butters are

a.	colloids.	c.	solutions.
b.	emulsions.	d.	suspensions.

____ 69. Which statement about bases is incorrect?

a.	All bases turn red litmus paper blue.	c.	All bases taste bitter.
b.	All bases contain hydroxide ions.	d.	All bases feel slippery.

____ 70. Acids are substances that

a.	form hydronium ions when dissolved in water.
b.	turn red litmus paper blue.
c.	make foods taste bitter.
d.	react with neutral liquids to form bases.

____ 71. When dissolved in water, all acids will

a.	form hydroxide ions.	c.	conduct electricity.
b.	have a negative charge.	d.	turn blue.

____ 72. A solution that is mildly acidic would have a pH of approximately

a.	2.	c.	6.
b.	4.	d.	8.

____ 73. The pH of a substance is a measure of its

a.	boiling point.	c.	ability to mix with water.
b.	food value.	d.	hydronium ion concentration.

____ 74. The label on a bottle indicates that the substance inside has a pH of 13. This tells you

that the substance is

a.	neutral.	c.	mildly basic.
b.	strongly acidic.	d.	strongly basic.

____ 75. When a solution of an acid reacts with a solution of a base, hydronium ions react with

hydroxide ions to form

a.	a salt.	c.	a weaker base.
b.	a stronger acid.	d.	water.

____ 76. When a solution of an acid reacts with a solution of a base, the pH of the resulting solution depends on the

a.	amounts of acid and base used.	c.	temperature of the acid and base used.
b.	concentration of base alone.	d.	concentration of acid alone.

____ 77. Which of the following is a basic solution?

a.	household ammonia	c.	vinegar
b.	HCl dissolved in water	d.	pure water

____ 78. What is a salt?

a.	a solution that contains a strong acid
b.	an ionic compound that does not contain oxide or hydroxide anions
c.	a substance formed by mixing two strong acids together
d.	a solution that contains more anions than cations and is strongly acidic

____ 79. Soap can remove grease and oil from your skin because it acts as

a.	an emulsifier to surround the oil.	c.	a solvent to dissolve the dirt.
b.	an acid to neutralize the dirt.	d.	a salt to make water harder.

____ 80. Which of the following is a base?

a.	lactose	c.	aspirin
b.	lemon juice	d.	baking soda

____ 81. Which is the strongest electrolyte?

a.	a weak base	c.	a neutral solution
b.	a strong acid	d.	a weak acid

____ 82. Which is an example of a neutralization reaction?

a.	NaOH ® Na⁺+ OH^-	c.	2H₂ + O₂ ® 2H₂O
b.	HNO₃ + H₂O ® H₃O⁺ + NO₃^-	d.	H₃O⁺ + OH^- ® 2H₂O

____ 83. Which are the spectator ions in the following reaction?

H₃O⁺ + Br^- + K⁺ + OH^– ® K⁺ + Br^- + 2H₂O

a.	H₃O⁺ and K⁺	c.	Br^- and K⁺
b.	Br^-and OH^-	d.	H₃O⁺ and OH^-

____ 84. Which substance, when added to milk, causes the milk to curdle?

a.	lemon juice	c.	baking soda
b.	yogurt	d.	sugar

____ 85. Ions that do not change during a chemical reaction are called

a.	spectator ions.	c.	monatomic ions.
b.	hydroxide ions.	d.	hydronium ions.

____ 86. Radioactive materials have unstable

a.	electrons.	c.	protons.
b.	nuclei.	d.	neutrons.

____ 87. Which of the following is not a type of nuclear radiation?

a.	alpha particles	c.	neutron emission
b.	beta particles	d.	X rays

____ 88. The type of nuclear radiation that can penetrate farthest through matter is called

a.	radons.	c.	neutron emission.
b.	gamma rays.	d.	X rays.

____ 89. The process of nuclear change in an atom of radioactive material is called

a.	nuclear decay.	c.	nuclear mass.
b.	isotopes.	d.	radon.

____ 90. Nuclear radiation refers to charged particles or energy emitted by an unstable

a.	proton.	c.	nucleus.
b.	atom.	d.	isotope.

Problem

91. The molar mass of nitrogen is 14.01 g/mol. The mass of 0.20 mol of nitrogen is ____________________ g.

92. The molar mass of palladium is 106.42 g/mol. Therefore, 53.2 g of palladium contains ____________________ mol.

93. Balance the following equation

FeO + CO Fe + CO

94. Balance the following Equation

NaS + Zn(NO) ZnS + NaNO

95. Write the chemical formula for magnesium and oxygen

96. Write the correct formula for CrCl

97. Write the name of PS a covalent compound

98. Classify the following reaction as a synthesis, decomposition, single-displacement or double-displacement

2Li + 2HO 2LiOH + H

99. What is the molarity of 250 mL of a solution that contains 12.5 g of dissolved zinc bromide

ZnBr?

100. How many moles of lithium chloride are dissolved in 3.00 L of a 0.200 M solution of lithium chloride?

Essay

101. Explain why atoms have no electric charge even though they are made up of charged particles.

102. Explain how a chemist defines a metal, and explain the difference between metals and nonmetals.

103. Describe how ionic, covalent, and metallic bonds differ from each other.

104. How is synthesis reaction different from decomposition reaction?

105. Explain why an alloy is a type of solution. Why are alloys used more often than pure metals?

106. Describe the difference between a suspension and an emulsion.

107. Describe some common household uses for acids and bases.

108. Describe a situation in which a scientist might want to use a short-lived isotope (tracers) like magnesium-28.

109. Name at least two disadvantages of a nuclear-fission reactor.

110. List several familar transition metals and their uses