Question 1

Which of the following elements is NOT among the most abundant in living cells?

Accepted Answer

Sulfur (S)

Question 2

A carbon atom has 4 electrons in its outermost shell. According to the octet rule, how many covalent bonds can a carbon atom typically form?

Accepted Answer

$$4$$

Question 3

Which type of bond is formed when two atoms share electrons equally?

Accepted Answer

Nonpolar covalent bond

Question 4

What property of an atom determines whether a covalent bond will be polar or nonpolar?

Accepted Answer

Electronegativity

Question 5

Which of the following best describes a hydrogen bond?

Accepted Answer

A weak attraction between a partially positive hydrogen atom and a partially negative atom in another molecule

Question 6

Water is a polar molecule. Which of the following statements best explains why?

Accepted Answer

Oxygen is more electronegative than hydrogen, creating partial charges

Question 7

Which of the following molecules is most likely to be hydrophobic?

Accepted Answer

A molecule with many nonpolar covalent bonds

Question 8

If the difference in electronegativity between two atoms is very large, what type of bond is most likely to form?

Accepted Answer

Ionic bond

Question 9

Which of the following best explains why salt (NaCl) dissolves easily in water?

Accepted Answer

Water's partial charges interact with the charged ions of NaCl, stabilizing them in solution

Question 10

Which of the following statements about macromolecules is TRUE?

Accepted Answer

Polysaccharides are made from monosaccharide monomers

Question 11

A molecule contains several C–H bonds. Which of the following best describes these bonds?

Accepted Answer

Nonpolar covalent bonds

Question 12

Which of the following is a correct statement about electron shells in atoms important for life?

Accepted Answer

The second shell can hold up to 8 electrons

Question 13

Which of the following best explains why carbon dioxide ($$CO_2) is $$considered nonpolar, even though it contains polar bonds?

Accepted Answer

The molecule is linear, so the partial charges cancel each other out

Question 14

Which of the following is an example of a hydrogen bond in biological systems?

Accepted Answer

The attraction between the oxygen atom of one water molecule and the hydrogen atom of another water molecule

Question 15

A molecule is described as hydrophilic. Which of the following is most likely TRUE about this molecule?

Accepted Answer

It forms hydrogen bonds with water

Question 16

Which of the following best describes the difference between ionic and covalent bonds?

Accepted Answer

Ionic bonds involve transferring electrons, while covalent bonds involve sharing electrons

Question 17

Which of the following is a correct pairing of a biological macromolecule and its monomer?

Accepted Answer

Nucleic acid – Nucleotide

Question 18

A molecule has a region with a partial positive charge and a region with a partial negative charge. Which term best describes this molecule?

Accepted Answer

Polar

Question 19

Which of the following statements about hydrogen bonds is FALSE?

Accepted Answer

Hydrogen bonds are stronger than covalent bonds

Question 20

Which of the following best explains why oil does not dissolve in water?

Accepted Answer

Oil molecules are nonpolar and cannot form hydrogen bonds with water

The Chemistry of Life: Atoms, Bonds, and Biological Macromolecules

Study Guide - Practice Questions