Multiple Choice

Choose the best answer.

Question 1

1. Sweet

2. Minty

3. Fishy

4. Putrid

Question 2

1. NH₄C₂H₃O₂

2. C(CH₃)₄

3. CH₂BrF

4. Na₂CO₃

Question 3

1. Valence electrons are shared between two metal atoms.

2. Valence electrons are shared between two nonmetal atoms.

3. Valence electrons are transferred from a metal atom to a nonmetal atom.

4. Valence electrons are transferred from a nonmetal atom to a metal atom.

Question 4

1. The two compounds will most likely smell different from each other because isomers have the same molecular formula but different structural formulas.

2. The two compounds will most likely smell the same because isomers have the same molecular formula but different structural formulas.

3. The two compounds will most likely smell the same because isomers have the same molecular formula and the same structural formulas.

4. The two compounds will most likely smell different from each other because isomers have different molecular formulas and the same structural formulas.

Question 5

1. The molecular formula for the molecule is C₉H₁₅O.

2. The functional group is an ester.

3. The shape around all of the carbon atoms is linear.

4. The name of the compound will most likely end with “-one.”

Question 6

1. The total number of dots surrounding the symbol is the number of valence electrons for that element.

2. The number of dots surrounding the symbol will be the same for all elements of the same group on the periodic table.

3. For elements in the same period on the periodic table, the number of dots surrounding the element symbol will increase as you move from left to right on the periodic table.

4. All of the above statements are true.

Question 7

1. The Lewis structure for CF₄ has a total of 40 dots in the structure because there are 5 atoms.

2. In the Lewis structure for CF₄, carbon is the central atom with four bonded pairs of electrons, and each fluorine atom has a total of three bonded pairs of electrons.

3. In the Lewis structure for CF₄, carbon is the central atom with four bonded pairs of electrons, and each fluorine atom has three lone pairs of electrons.

4. In the Lewis structure for CF₄, the fluorine atom shares seven electrons with each carbon atom.

Question 8

1. Water is a bent molecule that has two lone pairs around the central oxygen atom.

2. Water is a linear molecule that has two lone pairs around the central oxygen atom.

3. Water is a bent molecule with no lone pairs around the central oxygen atom.

4. Water is a bent molecule with no lone pairs around the central hydrogen atom.

Question 9

1. H₂, N₂, O₂, Cl₂

2. C₂H₂, C₂H₄, C₂H₆, H₂CO

3. O₂, C₂H₄, H₂CO

4. H₂, N₂, Cl₂, C₂H₆

Question 10

1. Six electrons

2. Five electrons

3. Four electrons

4. Three electrons

Question 11

1. The molecule has a carboxyl group, so it likely smells putrid.

2. The molecule has a carboxyl group, so it likely smells minty.

3. The molecule has an ester group, so it likely smells sweet.

4. The molecule has a ketone group, so it likely smells minty.

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Question 12

1. Only bonded pairs of electrons affect the shape of a molecule.

2. Only lone pairs of electrons affect the shape of a molecule.

3. Electron pairs have a tendency to repel one another due to their negative charge.

4. Electron pairs have a tendency to be as close to one another as possible.

Question 13

1. Pyramidal and bent

2. Tetrahedral and pyramidal

3. Tetrahedral and bent

4. Pyramidal and linear

Question 14

1. Smell molecules come in a variety of molecular shapes.

2. Smell molecules change phase to become a gas or vapor that floats through the air to enter your nose and be detected.

3. Smell molecules “dock” in receptor sites that match their molecular shapes.

4. Nerves are stimulated when the molecules dock and send messages to the brain, which are interpreted as a particular smell.

1. Smell molecules must break apart into individual atoms when they become a gas.

2. Smell molecules must lose their functional groups when they become a gas.

3. Smell molecules must change their shape to fit the “dock” in the receptor sites.

4. Smell molecules must keep their same structural formula when they become a gas.

Question 15

1. The C–H bonds are nonpolar covalent bonds because the electronegativity difference between carbon and hydrogen is large.

2. The C–H bonds are polar covalent bonds because the electronegativity difference between carbon and hydrogen is large.

3. The C–H bonds are ionic bonds because the electronegativity difference between carbon and hydrogen is large.

4. The polarity of C–H bonds is small because the electronegativity difference between carbon and hydrogen is small.

Question 16

1. NH₃

2. CCl₄

3. C₂H₆

4. CH₃OH

Question 17

1. Iodine, I₂, is more soluble in water than in oil.

2. Iodine, I₂, is more soluble in oil than in water.

3. Vinegar, CH₃COOH, is more soluble in oil than in water.

4. Sodium chloride, NaCl, is more soluble in oil than in water.

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Question 18

1. Water molecules form drops rather than spreading out on wax paper.

2. Water is a liquid at room temperature while methane is a gas at room temperature, even though both water and methane have similar molecular mass.

3. The O–H bond in water is polar because of differences in electronegativity of the atoms.

4. Oil tends to float on water while ethanol tends to dissolve in water.

Question 19

1. C, H, O

2. O, Cl, F

3. Ne, H, C

4. Cl, Br, I

Question 20

1. CH(CH₃)FBr

2. CHF₃

3. CH₂F₂

4. CF₄