Wayground logo

Free Printable Worksheets

Font size

S
M
L
XL
Worksheets

mass number and atomic number

Total questions: 19

Worksheet time: 13mins

Name
Class
Date
1.
What is the atomic number?
a)
the number of protons
b)
the number of protons and neutrons
c)
the number of neutrons
d)
the number of protons and electrons
2.
What is the mass number defined as?
a)
the number of protons
b)
the number of protons and neutrons
c)
the number of neutrons
d)
the number of protons and electrons
3.

How many protons are in a sodium atom, Na? (tap to enlarge the periodic table)

a)

Sodium has 1 proton.

b)

Sodium has 3 protons.

c)

Sodium has 11 protons

4.

Atoms of the same element which have a different number of neutrons are called _________________.

a)

ions

b)

isotopes

c)

quarks

d)

molecules

5.

Which subatomic particle has a negative charge in the atom?

a)

proton

b)

neutron

c)

electron

d)

quark

6.

How many neutrons does an atom of the isotope Neon-22 have? (tap to enlarge the image)

a)

12

b)

10

c)

22

d)

20

7.

If an atom has 10 electrons, how many protons does it have?

a)

0

b)

1

c)

10

d)

5

8.
Which particle has a positive charge?
a)
electron
b)
orbital
c)
proton
d)
neutron
9.
Choose the particle that has no charge.
a)
nucleus
b)
neutron
c)
proton
d)
electron
10.
Which particles make up the nucleus of an atom?
a)
protons and neutrons
b)
electrons and protons
c)
electrons, protons, and neutrons
d)
electrons and neutrons
11.

What is the Atomic Number of this Element

a)

7

b)

3

c)

4

d)

1

12.

What is the number of protons in Magnesium atom ?

a)

12

b)

24

c)

23

d)

8

13.

What is the number of electrons in chlorine atom ?

a)

35

b)

11

c)

18

d)

17

14.
How many neutrons does  Fluorine-19 contain?
a)
9
b)
19
c)
10
15.

What does the 1.00794 stand for?

a)

mass number

b)

atomic number

c)

average atomic mass

d)

number of protons

16.
If an atom has 10 protons, 10 neutrons, and 10 electrons, what is the mass of the atom?
a)
10
b)
20
c)
30
17.

What is the atomic number of this atom shown in the Bohr model?

a)

11

b)

12

c)

13

d)

can't be determined

18.

What is the mass number of the atom shown in the Bohr model?

a)

11

b)

12

c)

23

d)

Can't be determined

19.

Most of the mass of an atom is found in the ______.

a)

nucleus

b)

proton

c)

electron cloud

d)

isotope