$\text{Atomic mass} = \text{protons} + \text{neutrons}$

Question 1

Which of the following statements best explains why atoms are considered to be mostly empty space?

Accepted Answer

Because the nucleus is very small compared to the overall size of the atom, and electrons occupy a large region around it.

Question 2

If the nucleus of an atom were the size of a marble, approximately how far away would the electron be, according to the analogy provided?

Accepted Answer

As far away as a keyboard, and be as small as a keyboard key.

Question 3

Which subatomic particles are found in the nucleus of an atom?

Accepted Answer

Protons and neutrons

Question 4

What is the correct formula for calculating the atomic mass of an element?

Accepted Answer

$	ext{Atomic mass} = 	ext{protons} + 	ext{neutrons}$

Question 5

A carbon atom has 6 protons and 7 neutrons. What is its atomic mass?

Accepted Answer

$6 + 7 = 13$

Question 6

Which of the following best describes isotopes?

Accepted Answer

Atoms of the same element with different numbers of neutrons

Question 7

Which element makes up the largest percentage of the human body by mass?

Accepted Answer

Oxygen

Question 8

Given the periodic table, what does the atomic number of an element represent?

Accepted Answer

The number of protons in the nucleus

Question 9

Which of the following elements is considered a trace element in the human body?

Accepted Answer

Iron (Fe)

Question 10

If an atom has 11 protons, 12 neutrons, and 11 electrons, what is its atomic mass and which element is it?

Accepted Answer

Atomic mass = $11 + 12 = 23$; Element: Sodium (Na)

Question 11

Which of the following is NOT one of the four most abundant elements in living organisms?

Accepted Answer

Phosphorus

Question 12

A neutral atom of helium has how many electrons?

Accepted Answer

2

Question 13

Which of the following best explains why isotopes of the same element behave similarly in chemical reactions?

Accepted Answer

They have the same number of electrons and protons.

Question 14

Which of the following is the correct representation for the atomic symbol, atomic number, and atomic mass of helium?

Accepted Answer

Atomic number: 2, Atomic symbol: He, Atomic mass: 4.00

Question 15

Which of the following statements about electrons is TRUE?

Accepted Answer

Electrons form a cloud around the nucleus and are responsible for chemical bonding.

Question 16

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

Accepted Answer

A proton

Question 17

Which of the following elements is NOT classified as a trace element in the human body?

Accepted Answer

Magnesium (Mg)

Question 18

Which of the following best describes the relationship between protons and electrons in a neutral atom?

Accepted Answer

The number of protons equals the number of electrons.

Question 19

Which of the following is a correct statement about the periodic table?

Accepted Answer

Elements are arranged by increasing atomic number.

Question 20

A patient is diagnosed with anemia due to iron deficiency. Which category does iron (Fe) fall under in terms of its abundance in the human body?

Accepted Answer

Trace element

Atoms, Elements, and the Chemical Basis of Life: Study Notes for General Biology

Study Guide - Practice Questions