Question 1

Which of the following statements best describes an atom?

Accepted Answer

An atom is the smallest unit of a chemical element and the smallest unit of matter.

Question 2

Which subatomic particle has a positive charge and is found in the nucleus of an atom?

Accepted Answer

Proton

Question 3

What is the atomic number of an element equal to?

Accepted Answer

The number of protons only

Question 4

A neutral oxygen atom has an atomic number of 8 and a mass number of 16. How many neutrons does it have?

Accepted Answer

$$8$$

Question 5

Which of the following elements is NOT one of the six most abundant elements in living organisms (CHNOPS)?

Accepted Answer

Calcium

Question 6

How many electrons can the first energy shell of an atom hold?

Accepted Answer

$$2$$

Question 7

According to the octet rule, why is neon (Ne) unreactive?

Accepted Answer

Its valence shell is full of electrons.

Question 8

How many electrons does an oxygen atom need to fulfill the octet rule by filling its valence shell?

Accepted Answer

$$2$$

Question 9

What is an isotope?

Accepted Answer

Atoms of the same element with different numbers of neutrons.

Question 10

Carbon-13 and Carbon-14 are isotopes of carbon. How do they differ from Carbon-12?

Accepted Answer

Each has an extra neutron.

Question 11

A radioactive isotope has a half-life of 5,730 years. How many years must pass for a sample to break down to $$\frac{1}{4} of $$its original amount?

Accepted Answer

$$11,460$$ years

Question 12

Which of the following is NOT a use of radioactive isotopes?

Accepted Answer

Increasing the stability of molecules

Question 13

What type of bond is formed when two atoms share a pair of electrons?

Accepted Answer

Covalent bond

Question 14

Which of the following best describes a nonpolar covalent bond?

Accepted Answer

Electrons are shared equally between atoms.

Question 15

If a covalent bond is polar, what is true about the atoms involved?

Accepted Answer

One atom has a partial negative charge.

Question 16

What type of bond holds the hydrogens and oxygen together within a water molecule?

Accepted Answer

Covalent bond

Question 17

Which of the following is a very weak non-covalent chemical bond?

Accepted Answer

Van der Waals bond

Question 18

What is the main difference between an anion and a cation?

Accepted Answer

An anion has more electrons than protons.

Question 19

Which of the following best describes an ionic bond?

Accepted Answer

Atoms of opposite charges attract each other.

Question 20

Which property of the bond between hydrogen and oxygen in a water molecule makes it polar?

Accepted Answer

Oxygen is more electronegative than hydrogen.

Bonding and Atomic Structure in Organic Compounds: Foundations for Organic Chemistry

Study Guide - Practice Questions