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Atoms (Protons, Neutrons Electtons, Isotopes Average Atomic Mass

Total questions: 66

Worksheet time: 3hrs 39mins

Name
Class
Date
1.

24.1% of all the isotopes of a an element have a mass of 75.23 amu, 48.7% have a mass of 74.61 amu, and 27.2% have a mass of 75.20 amu.
What is the average mass of this element?

a)

74.92 amu

b)

24.97 amu

c)

75.01 amu

d)

74.51 amu

2.

24.1% of all the isotopes of a an element have a mass of 75.23 amu, 48.7% have a mass of 74.61 amu, and 27.2% have a mass of 75.20 amu.
How many protons does this element have?

a)

32

b)

33

c)

34

d)

no way to know

3.

Calcium has three different isotopes. One has a mass of 35.00 amu; another has a mass of 41.00 amu; and another has a mass of 40.00 amu. Which isotope is the most abundant of the three?

a)

40.00 amu

b)

41.00 amu

c)

35.00 amu

d)

impossible to tell

4.

An element has three different isotopes. One has a mass of 35.00 amu; another has a mass of 36.00  amu; and another has a mass of 38.00  amu. What is the average atomic mass of this element?

a)

36.33 amu

b)

37.00 amu

c)

12.11 amu

d)

impossible to tell

5.

An element with 4.35% have a mass of 49.9461 amu, 83.79% have amass of 51.9405 amu, 9.50% have a mass of 52.9407 amu, and 2.36% have a mass of 53.9389amu.

a)

51.99 amu

b)

52.19 amu

c)

53.45 amu

d)

17.33 amu

6.

4.35% of all X atoms have a mass of 39.946 amu. 83.79% have a mass of 41.941 amu, 9.50% have a mass of 42.941 amu, and 2.36% have a mass of 43.939 amu. What is the average atomic mass of atom X?

a)

41.97 amu

b)

42.19 amu

c)

10.43 amu

d)

40.04 amu

7.

An isotope has three forms.  30% have a mass of 4 amu, 20% have a mass of 5 amu and 50% have a mass of 3 amu.  Average atomic mass will be closest to

a)

2 amu

b)

3 amu

c)

4 amu

d)

5 amu

8.

Calculate the average atomic mass of silver.

a)

106.38649amu

b)

111.91896amu

c)

107.8677amu

d)

121

9.

Nitrogen has three occurring isotopes: Nitrogen-13, Nitrogen-14, Nitrogen-15. Which isotope is the most abundant?

a)

Nitrogen-13

b)

Nitrogen-14

c)

Nitrogen-15

d)

Based on the information given, it cannot be determined

10.

Ions are: 

a)

atoms with a positive or negative charge

b)

atoms with no charge

c)

atoms with ONLY a positive charge

d)

atoms with ONLY a negative charge

11.

An element has two naturally occurring isotopes. One is 10.013 amu and is 19.9% abundant. The other is 11.01 amu and is 80.1% abundant. What is the average atomic mass? What element is it?

a)

9.012, Beryllium

b)

12.011, Carbon

c)

6.941, Lithium

d)

10.812, Boron

12.

A neutral atom of Carbon-13 has ________ electrons and _________ neutrons

a)

13, 13

b)

6, 7

c)

7, 7

d)

6, 6

13.

The  mass of an atom is located  in the ___________ and the volume of an atom is made of the ____________

a)

electron cloud, nucleus

b)

electron cloud, energy levels

c)

nucleus, electron cloud

d)

nucleus, neutrons

14.

Do the following atoms belong to the same element? Explain
       Aluminum-27
       An atom with 14 protons and 13 neutrons

a)

Yes because they have the same number of protons

b)

Yes because they have the same mass

c)

No because they have different number of protons

d)

No because they have different number of neutrons

15.

What do carbon-12 and carbon-14 have in common?

a)

they have same number of protons

b)

they have the same number of neutrons

c)

they have the same atomic mass

d)

they have the same atomic weight

16.

What does the 1.00794 stand for?

a)

Hydrogen

b)

atomic number

c)

atomic mass

d)

atomic explosion

17.

What is the atomic number for an element with three protons?

a)

2

b)

1

c)

3

d)

6

18.

An isotope has three forms.  30% have a mass of 4 amu, 20% have a mass of 5 amu and 50% have a mass of 3 amu.  Average atomic mass will be closest to

a)

2 amu

b)

3 amu

c)

4 amu

d)

5 amu

19.

An element has two naturally occurring isotopes. One is 10.013 amu and is 19.9% abundant. The other is 11.01 amu and is 80.1% abundant. What is the average atomic mass? What element is it?

a)

9.012, Beryllium

b)

12.011, Carbon

c)

6.941, Lithium

d)

10.812, Boron

20.

Compute the average atomic mass for silicon:

a)

27.977

b)

28.09

c)

28.976

d)

The average mass cannot be determined from provided information.

21.

A neutral atom of Carbon-13 has ________ electrons and _________ neutrons

a)

13, 13

b)

6, 7

c)

7, 7

d)

6, 6

22.

Isotopes are atoms of the same element that have the same number of __________ but different number of __________ . Therefore, isotopes of the same element have different masses. 

a)

protons, neutrons

b)

protons, electrons

c)

neutrons, protons

d)

electrons, protons

23.

The  mass of an atom is located  in the ___________ and the volume of an atom is made of the ____________

a)

electron cloud, nucleus

b)

electron cloud, energy levels

c)

nucleus, electron cloud

d)

nucleus, neutrons

24.

What is the atomic number of Neon, Ne?

a)

10

b)

20.1798

c)

10.1798

d)

7

25.

A neutral atom of the isotope 2612Mg would consist of

a)

12 protons, 26 neutrons, 26 electrons

b)

26 protons, 12 neutrons, 26 electrons

c)

26 protons, 14 neutrons, 14 electrons

d)

12 protons, 14 neutrons, 12 electrons

26.

A neutral atom would become an ion that has a charge of 2+ by 

a)

Losing two protons

b)

Losing two neutrons

c)

Losing two electrons

27.

4.35% of all X atoms have a mass of 39.946 amu. 83.79% have a mass of 41.941 amu, 9.50% have a mass of 42.941 amu, and 2.36% have a mass of 43.939 amu. What is the average atomic mass of atom X?

a)

41.97 amu

b)

42.19 amu

c)

10.43 amu

d)

40.04 amu

28.

Naturally occurring chlorine that is put in pools is 75.53 percent 35Cl (mass = 34.969 amu) and 24.47 percent 37Cl (mass = 36.966 amu). Calculate the average atomic mass.

a)

35.46 amu

b)

35.00 amu

c)

37.00 amu

d)

17.00 amu

29.

An element with 4.35% have a mass of 49.9461 amu, 83.79% have amass of 51.9405 amu, 9.50% have a mass of 52.9407 amu, and 2.36% have a mass of 53.9389amu.

a)

51.99 amu

b)

52.19 amu

c)

53.45 amu

d)

17.33 amu

30.

The atomic mass of an element is the ___.

a)

average of the mass number and the atomic number for the element

b)

weighted average of the masses of the isotopes of the element

c)

total mass of the isotopes of the element

d)

total number of subatomic particles in the nucleus

31.

Chlorine has two naturally occurring isotopes, Cl-35 and Cl-37, The atomic mass of chlorine is 35.45. Which of these two isotopes of chlorine is more abundant?

a)

Cl-35

b)

Cl-37

c)

Cannot be determined from the information provided.

32.

An element has three isotopes. Given the abundances and relative masses, calculate the average atomic mass and determine (from the periodic table) which element it is.


Abundances | Relative masses

0.005% | 234.04 amu

0.720% | 235.04 amu

99.275% | 238.05 amu

a)

Uranium (#92, Atomic Mass: 238.03 amu)

b)

Fluorine (#9, Atomic Mass: 19.00 amu)

c)

Mercury (#89, Atomic Mass: 200.59 amu)

d)

Polonium (#84 209 amu)

33.

Element Z has 2 natural isotopes. One isotope has a mass of 15.0 amu and a relative abundance of 30%. The other isotope has a mass of 16.0 amu and a relative abundance of 70%. Estimate the average atomic mass for this one element.

a)

15.0 amu

b)

16.0 amu

c)

15.7 amu

d)

16.9 amu

34.

Calcium has three different isotopes. One has a mass of 35.00 amu; another has a mass of 41.00 amu; and another has a mass of 40.00 amu. Which isotope is the most abundant of the three?

a)

40.00 amu

b)

41.00 amu

c)

35.00 amu

d)

impossible to tell

35.

What is the mass of a carbon atom that has 6 protons, 7 neutrons, and 6 electrons?

a)

6

b)

7

c)

13

d)

19

36.

An atom of tin has an atomic number of 50 and a mass number of 119. How many protons, electrons, and neutrons are found in one neutral atom of tin?

a)

50 protons, 69 electrons, 50 neutrons

b)

50 protons, 50 electrons, 69 neutrons

c)

69 protons, 50 electrons, 69 neutrons

d)

69 protons, 69 electrons, 50 neutrons

37.

Subatomic particles with a negative charge

a)

Electrons

b)

Neutrons

c)

Protons

d)

Quarks

38.

How many neutrons does calcium have?

a)

20

b)

40

c)

60

d)

0

39.

Atoms of the same element with different numbers of neutrons are called

a)

Ions

b)

Isotopes

c)

Iotas

d)

Introns

40.

To calculate average atomic mass, you need

a)

the atomic mass of each isotope

b)

the percent abundance of each isotope

c)

the atomic mass and percent abundance of each isotope

d)

to find the average of the atomic masses of each isotope

41.

Which subatomic particle determines the identity of an element?

a)

protons

b)

neutrons

c)

electrons

42.

An atom that has a different number of protons and electrons is a(n)

a)

Neutral Atom

b)

Ion

c)

Isotope

43.

Match the following

a)

proton

1.

positive charge

b)

neutron

2.

no charge

c)

electron

3.

negative charge

44.

How many protons?

a)

92

b)

235

c)

143

45.
In order for me to find the number of neutrons, I must round the atomic mass and then do what?
a)
atomic number-atomic mass
b)
atomic number x atomic mass
c)
atomic mass + atomic number
d)
atomic mass - atomic number
46.

How many electrons are in Sulfur?

a)

32

b)

16

c)

48

d)

8

47.

Which would you do to change this Lithium to a new element?

a)

Add a neutron

b)

Add an electron

c)

Add a proton

d)

Add a proton and neutron\

48.

An atom that has more protons then electrons are called

a)

cations

b)

anions

c)

isotopes

d)

molecules

49.

Isotopes are atoms with a different number of

a)

protons

b)

electrons

c)

neutrons

d)

atoms

50.

Potassium is a metal, therefore it will

a)

lose electrons

b)

gain electrons

51.

How is average atomic mass determined?

a)

By adding all of the protons and neutrons together.

b)

by summing the masses of the element's isotopes, each multiplied by its natural abundance on Earth

c)

By multiplying of often protons and neutrons occur and adding up the averages.

52.

What are AMU's

a)

Atomic Mass University

b)

Atomic Mass Units

c)

Atoms mean unity

d)

All Mass United

53.

If an atom has 5 protons and 6 neutrons what is the proper name of the isotope?

a)

Boron-1

b)

Boron-11

c)

Carbon-11

d)

Carbon 11

e)

Boron Carbonate

54.
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
55.
How many neutrons in C-14?
a)
6
b)
7
c)
14
d)
8
56.
Four isotopes of lead include lead-204, lead-206, lead-207, and lead-208.  The average atomic mass of lead is 207.2.  Which isotope of lead is likely to be the most abundant.
a)
204
b)
206
c)
207
d)
208
57.

Which atom will have a +1 charge?

a)

3 protons

4 neutrons

3 electrons

b)

3 protons

4 neutrons

4 electrons

c)

3 protons

4 neutrons

2 electrons

d)

3 protons

3 neutrons

3 electrons

58.

How many electrons are present in this atom?

a)

36

b)

17

c)

19

d)

18

59.

Potassium-39 has how many neutrons?

a)

19

b)

18

c)

20

d)

21

60.

76 protons and 114 neutrons

a)

Osmium-114

b)

Osmium-76

c)

Osmium-190

d)

Osmium-190.23

61.

9 protons and 9 neutrons

a)

Fluorine-18

b)

Fluorine-9

c)

Fluorine-16

d)

Fluorine-18.998

62.

What is the difference between Neon-20 and Neon-22?

a)

They have different numbers of electrons.

b)

They have different numbers of neutrons.

c)

Only 1 is radioactive.

d)

No difference.

63.

ALL atoms of the same element have:

a)

same number of proton

b)

same number of nucleon

c)

different number of neutron

d)

different number of electron

64.
The number of protons is equal to 
a)
the atomic number
b)
the number of neutrons
c)
the energy levels
d)
the periodic table groups
65.

Which is true of the following beryllium atom?

a)

4 protons and 9 neutrons

b)

5 neutrons and 4 electrons

c)

9 protons and 4 neutrons

d)

4 protons and 2 electrons

66.

The nuclear symbol for an element is, 7735X . Match the following information:

a)

Atomic Number

1.

35

b)

Mass Number

2.

77

c)

Neutrons

3.

42