Question 1

Which of the following best describes a compound?

Accepted Answer

A substance consisting of two or more different elements chemically bonded in fixed proportions.

Question 2

What is the atomic number of sodium, and what does it represent?

Accepted Answer

11; it represents the number of protons.

Question 3

If a neutral atom of carbon has an atomic number of 6 and an atomic mass of 12, how many neutrons does it have?

Accepted Answer

6

Question 4

Which subatomic particle determines the chemical properties and reactivity of an atom?

Accepted Answer

Electron

Question 5

What happens to an atom if the number of protons is changed?

Accepted Answer

It becomes a different element.

Question 6

Which of the following bonds is formed when electrons are shared unequally between atoms?

Accepted Answer

Polar covalent bond

Question 7

Given the electron configuration for oxygen ($1s^2 2s^2 2p^4$), how many covalent bonds can oxygen typically form?

Accepted Answer

2

Question 8

Which of the following is true about hydrogen bonds?

Accepted Answer

They are important for the structure of water and biological macromolecules.

Question 9

A fluorine atom has 9 protons, 10 neutrons, and 9 electrons. What is its atomic mass?

Accepted Answer

$19$

Question 10

Which of the following best describes a valence shell electron?

Accepted Answer

An electron in the outermost shell that determines chemical reactivity.

Question 11

If a hydrogen atom loses its only electron, what is the resulting particle called?

Accepted Answer

Hydrogen ion ($H^+$)

Question 12

Which of the following is NOT one of the 'big 4' elements of life?

Accepted Answer

Sodium

Question 13

What is the charge of a sodium ion after it loses one electron?

Accepted Answer

$+1$

Question 14

Which type of bond is responsible for the attraction between water molecules?

Accepted Answer

Hydrogen bond

Question 15

If the number of neutrons in an atom changes, what is the result?

Accepted Answer

An isotope is formed.

Question 16

Which of the following best explains why noble gases are chemically inert?

Accepted Answer

They have a full valence electron shell.

Question 17

A molecule of methane ($CH_4$) contains how many covalent bonds?

Accepted Answer

$4$

Question 18

Which of the following statements about ionic bonds is correct?

Accepted Answer

They result from the transfer of electrons from one atom to another.

Question 19

If the atomic number of an element is 8 and its atomic mass is 16, how many neutrons does it have?

Accepted Answer

$8$

Question 20

Which of the following best describes potential energy in the context of electrons?

Accepted Answer

The energy electrons have due to their position relative to the nucleus.

Atoms, Elements, and Chemical Bonds: Study Notes for General Biology

Study Guide - Practice Questions