Chapter Three, Lesson One: Introduction to Atoms

Question 1

atom

Answer 1

In modern terms, an atom is the smallest particle that can still be considered an element.

Question 2

electrons

Answer 2

Atoms contain negatively charged particles called electrons.

Question 3

nucleus

Answer 3

An atom’s positive charge is packed within a small region in its center, called the nucleus.

Question 4

protons

Answer 4

The positively charged particles in an atom’s nucleus are called protons.

Question 5

energy level

Answer 5

An electron’s movement is related to its energy level, or the specific amount of energy it has.

Question 6

neutron

Answer 6

A neutron is hard to find because it has no electric charge.

Question 7

atomic number

Answer 7

The number of protons in the nucleus of an atom is the atomic number of that atom’s element.

Question 8

isotopes

Answer 8

Atoms with the same number of protons and different numbers of neutrons are called isotopes.

Question 9

mass number

Answer 9

An isotope is identified by its mass number, which is the sum of the protons and neutrons in the atom.