CHE 022 ACTIVITY LESSON 9

What is the atomic number of an element?

• a. Number of protons

• b. Number of neutrons

• c. Number of electrons

• d. Number of protons and neutrons combined

2. The mass number of an atom is equal to:

• a. Number of protons

• b. Number of electrons

• c. Number of neutrons

• d. Number of protons and neutrons combined

How can you calculate the number of neutrons in an atom?

• Atomic number - Mass number

• Mass number - Atomic number

• Atomic number + Mass number

• Atomic number x Mass number

If an atom has 16 protons and 18 neutrons, what is its atomic mass?

• a. 16

• b. 18

• c. 34

• d. 54

Which subatomic particle is responsible for the chemical properties of an element?

• a. Proton

• b. Neutron

• c. Electron

• d. Nucleus

The nucleus of an atom contains:

• a. Protons and electrons

• b. Protons and neutrons

• c. Electrons and neutrons

• d. Electrons, protons, and neutrons

What is the charge of a proton?

• a. Positive

• b. Negative

• c. Neutral

• d. Variable

How many protons are there in an atom with an atomic number of 20?

• a. 10

• b. 20

• c. 40

• d. 60

If an atom has 25 electrons and its atomic number is 30, how many protons does it have?

• a. 5

• b. 25

• c. 30

• d. 55

Which of the following represents the correct notation for an atom with 8 protons, 8 neutrons,and 8 electrons?

• a. 8O

• b. O8

• c. 16O

• d. 8/8O