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Atomic and mass numbers

Total questions: 30

Worksheet time: 24mins

Name
Class
Date
1.

If the atomic number of Pb (Lead) is 82 and its atomic mass is 205, how many neutrons does it have?

a)

123

b)

82

c)

205

d)

287

2.

Hydrogen has an atomic mass of 3 and atomic number of 1. How many protons and neutrons does hydrogen have?

a)

3 protons and 1 neutron

b)

1 proton and 2 neutrons

c)

2 protons and 1 neutron

d)

1 proton and 3 neutrons

3.

Which element is the heaviest?

a)

Na

b)

Ar

4.

Which atom has an atomic mass of 16?

a)

Na

b)

Ar

c)

Ca

d)

O

5.

An atom has an atomic number of 11 and an atomic mass of 23. Which of the following statements is correct?

a)

It has 11 protons and 11 neutrons.

b)

It has 11 electrons and 12 protons.

c)

It has 11 protons and 11 electrons.

d)

It has 23 protons and 11 electrons.

6.

Which pair of particles contributes the most to the overall mass of the atom?

a)

Electrons and protons

b)

Protons and neutrons

c)

Electrons and neutrons

7.

The fluorine atom has an atomic number of

a)

19

b)

9

8.

The fluorine atom has an atomic number of

a)

19

b)

9

9.

What is the mass number and atomic number ?

a)

Mass number = 7, atomic number = 14

b)

Mass number = 14, atomic number = 7

10.

In an element box, the number at top is the

a)

atomic number

b)

atomic name

c)

atomic mass

d)

atomic symbol

11.

The chemical symbol in this element box is

a)

26

b)

Fe

c)

Iron

d)

55.845

12.

What does the arrow for #14 represent?

a)

Element Name

b)

Symbol

c)

Atomic Number

13.

What does the arrow for #15 represent?

a)

Symbol

b)

Element Name

c)

Atomic Mass

14.

If hydrogen has 1 proton and 1 neutron, the atomic number = ----

a)

1

b)

2

15.

If hydrogen has 1 proton and 1 neutron, the mass number = ----

a)

1

b)

2

16.

What is the mass number of this atom?

a)

1

b)

3

c)

4

d)

7

17.
What is the atomic number of this atom?
a)
1
b)
3
c)
4
d)
7
18.
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
19.
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
20.

An element has the mass number 12 and atomic number 6. The number of neutrons in it is:

a)

6

b)

10

c)

4

d)

8

21.

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

a)

ions

b)

isotopes

c)

quarks

d)

molecules

22.

Isotopes have different numbers of

a)

protons

b)

neutrons

c)

electron

d)

properties

23.

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

a)

0

b)

1

c)

10

d)

5

24.

How many electrons are in an atom with an atomic number of 50?

a)

5

b)

8

c)

50

d)

2

25.
Atom 1 has Mass=12  Protons=6
Atom 2 has Mass= 14 Electrons=6
Are these atoms isotopes of each other or different elements?
a)
Different Elements - Mg & Si
b)
Different Elements - Ar & Ca
c)
Isotopes of Carbon
d)
Isotopes of Magnesium
26.
The mass of one proton is equal to the mass of one...
a)
neutron
b)
electron
27.
All of the mass of an atom comes from what location?
a)
nucleus
b)
electron cloud
28.
The mass of one proton is greater than the mass of one...
a)
neutron
b)
electron
29.
What do these isotopes of carbon all have in common?
a)
neutrons & mass number
b)
atomic number and neutrons
c)
atomic number and electrons
d)
protons, atomic number, and mass number
30.
How many neutrons does the isotope of lithium have?
a)
8
b)
3
c)
4
d)
5