Question 1

Which subatomic particle is responsible for the bonding ability of an atom, and where is it located?

Accepted Answer

Electron; located in orbitals around the nucleus

Question 2

A neutral atom of carbon has 6 protons and 6 neutrons. What is its atomic mass?

Accepted Answer

$$12$$

Question 3

Which statement best describes an isotope?

Accepted Answer

An atom with the same number of protons but a different number of neutrons

Question 4

Which of the following best explains why water is a good solvent for many biochemical reactions?

Accepted Answer

Water is polar and can dissolve ionic and polar molecules

Question 5

What is the main difference between polar covalent and nonpolar covalent bonds?

Accepted Answer

Polar covalent bonds share electrons unequally, while nonpolar covalent bonds share electrons equally

Question 6

Which of the following equations correctly represents the dissociation of hydrochloric acid ($$\mathrm{HCl}) in $$water?

Accepted Answer

$$\mathrm{HCl} \rightarrow \mathrm{H}^+ + \mathrm{Cl}^-$$

Question 7

A solution has a pH of 4. Which of the following statements is true?

Accepted Answer

The solution is acidic and has a high concentration of $$\mathrm{H}^+$$ ions

Question 8

Which property of water allows ice to float on liquid water, and why is this important for aquatic life?

Accepted Answer

Water's lower density as a solid; ice insulates and moderates temperature flux

Question 9

Which of the following best describes the role of buffers in biological systems?

Accepted Answer

Buffers maintain a constant pH by neutralizing excess acids or bases

Question 10

If a molecule is formed by the bonding of two different atoms, and the electrons are shared unequally, what type of bond is present?

Accepted Answer

Polar covalent bond

Question 11

Which of the following is a correct statement about chemical reactions?

Accepted Answer

Chemical reactions rearrange atoms to form new molecules

Question 12

Which of the following best explains why water has a high specific heat?

Accepted Answer

Hydrogen bonds between water molecules require more energy to break

Question 13

A molecule of $$\mathrm{NaCl}$$ dissolves in water. What type of bond is broken during this process?

Accepted Answer

Ionic bond

Question 14

Which of the following best describes the relationship between atomic number and the number of protons in an atom?

Accepted Answer

Atomic number equals the number of protons

Question 15

Which of the following is true about hydrogen bonds?

Accepted Answer

They form between polar molecules, such as water

Question 16

A buffer solution contains a weak acid and its corresponding base. What is its primary function in a biological system?

Accepted Answer

To maintain a stable pH by neutralizing added acids or bases

Question 17

Which of the following best explains why surface tension occurs in water?

Accepted Answer

Water molecules at the surface are hydrogen-bonded to other water molecules below

Question 18

Which of the following is a consequence of water's high heat of vaporization for living organisms?

Accepted Answer

It helps regulate temperature by requiring more energy to convert liquid water to gas

Question 19

Which of the following best describes the role of reactants in a chemical reaction?

Accepted Answer

Reactants are the starting molecules that undergo change during a reaction

Question 20

Which of the following is true about acids and bases?

Accepted Answer

Strong acids ionize fully in solution, while weak acids do not

Fundamental Concepts in General Biology: Atoms, Molecules, Chemical Bonds, and Water

Study Guide - Practice Questions