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Structure & History of Atom

Total questions: 55

Worksheet time: 41mins

Name
Class
Date
1.

The three subatomic particles are

a)

proton, neutron, electron

b)

proton, nucleus, electron

c)

protein, neutron, electricity

d)

proton, neutral, electives

2.

99.9% of the atom's mass is found where?

a)

nucleus

b)

protons

c)

electron cloud

d)

neutrons

3.

Electrons are

a)

negative

b)

positive

c)

neutral

4.

Protons are

a)

negative

b)

positive

c)

neutral

5.

Neutrons are

a)

negative

b)

positive

c)

neutral

6.

When an atom contains more electrons than protons, it is

a)

a neutral atom with no charge

b)

an ion and negatively charged

c)

an ion and positively charged

d)

an isotope and has more mass

7.

When an atom contains more neutrons than another atom, it is

a)

a neutral atom with no charge

b)

an ion and negatively charged

c)

an ion and positively charged

d)

an isotope and has more mass

8.

The nucleus is ____________ charged.

a)

positively

b)

negatively

c)

neutral

9.

The area around the nucleus of an atom where the atom's electrons are most likely to be found is called

a)

electron cloud

b)

quark

c)

electron

d)

nucleus

10.

If a carbon atom has six protons and has a mass of 13 amu, how many neutrons are in that carbon atom?

a)

5

b)

6

c)

7

d)

8

11.

If a neutral atom has 8 protons, how many electrons does it have?

a)

7

b)

8

c)

9

d)

10

12.

A chemical symbol represents the _________ of an element.

a)

name

b)

structure

c)

reaction

d)

type

13.

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

a)

metalloids

b)

transition elements

c)

radioactive

d)

isotopes

14.

A certain atom has 26 protons, 26 electrons, and 30 neutrons. What is its mass number?

a)

26

b)

30

c)

52

d)

56

15.

What is 'E' pointing to?

a)

electron cloud

b)

electron

c)

nucleus

d)

proton

e)

neutron

16.

Electrons can best be described as having a

a)

large size, positive charge.

b)

very small size, positive charge.

c)

large size, negative charge.

d)

very small size, negative charge.

17.

Electrons are subatomic particles that exist

a)

inside the nucleus.

b)

in simultaneous dimensions.

c)

in parallel universes.

d)

outside the nucleus.

18.

Neutrons (discovered by James Chadwick in 1932) are neutral subatomic particles that are located

a)

in and outside the nucleus.

b)

in the nucleus.

c)

just outside the nucleus.

d)

in alternate universes.

19.

Neutrons have almost exactly the same mass as

a)

electrons.

b)

positrons.

c)

protons.

d)

quarks.

20.

James Dalton proved that the true nature of the atom could best be described as resembling "plum pudding."

a)

True

b)

False

21.

Rutherford proved the existence of protons located in a very small nucleus by using a crude particle accelerator in 1911.

a)

True

b)

False

22.

The atomic number (#) of an element is equal to the

a)

weight of an electron.

b)

# of neutrons in a single atom of that element.

c)

weight of a neutron.

d)

# of protons in a single atom of that element.

23.

Atoms of different elements have

a)

the same # of protons.

b)

the same general properties.

c)

a different # of protons.

d)

the same # of electrons.

24.

Because atoms are neutral, each positive charge is

a)

the same as a neutral charge.

b)

balanced by a negative charge.

c)

the same as no charge.

d)

balanced by a neutral charge.

25.

Which statement best describes the mass number (#) of an atom?

a)

the sum of electrons and neutrons in the nucleus

b)

the sum of protons & neutrons in the nucleus

c)

the difference in mass between protons & neutrons

d)

the difference in mass between electrons and neutrons

26.

Since atoms are balanced with equal #'s of positive & negative charges, the atomic # is also

a)

the same as the # of electrons.

b)

the # of neutrons in a single atom.

c)

the same as the # of neutrons.

d)

the # of electrons in a single atom.

27.

If you know the atomic number (or # of protons) and mass number of an atom, you can find the

a)

number of electrons by adding to the mass number.

b)

number of neutrons by adding to the mass number.

c)

number of neutrons by subtracting from the mass number.

d)

total atomic weight of an atom.

28.

If the atomic mass of an element is 32 and the atomic # is 16, then

a)

the number of neutrons is also 16.

b)

the element most likely has isotopes.

c)

the number of electrons is also 16.

d)

the number of protons is also 32.

29.

Every neutral atom has the same number of protons and electrons, however

a)

they may not have the same # of neutrons.

b)

they cannot combine with other atoms.

c)

they cannot form isotopes.

d)

they may also have the same atomic mass.

30.

Which statement best describes an isotope of an element?

a)

they share an equal amount of neutrons

b)

they have the same atomic #'s but with different mass #'s

c)

they have the same mass #'s but with different atomic #'s

d)

they have a different # (number) of protons

31.

How many neutrons are in the isotope pictured above?

a)

29

b)

34

c)

63

d)

92

32.

What is the number of protons in phosphorus-31?

a)

15

b)

16

c)

31

d)

46

33.

Element Q has 56 protons and 18 neutrons.

Element R has 56 protons and 17 neutrons. These elements are:

a)

different elements

b)

isotopes

34.
What is the number of protons that the element in this image contain?
a)
14
b)
7
c)
15
d)
18
35.
Which of the following is a substance that can not be broken down into a simpler substance?
a)
Isotope
b)
Element
c)
Compound
d)
Atomic Number
36.
What number indicates an electron?
a)
1
b)
2
c)
3
d)
4
37.

Mass minus Atomic Number Equals (M-A=?)

a)

Neutrons

b)

Protons

c)

Nucleus

d)

Atom

38.

The electron is not included in the calculations for the atomic mass because

a)

It has negative charge

b)

It is located in the outer energy levels of the atom

c)

It is nearly massless

d)

It attracts neutral particles

39.

AMU is the abbreviation for...

a)

atoms mostly unseen

b)

atomic mass unit

c)

atomic minded universe

d)

atom mixture unit

40.

What is the number of protons (atomic number) for this element?

a)

10

b)

20

c)

20.180

d)

30

41.

What is the number of protons (atomic number) for this element?

a)

167

b)

167.26

c)

68

d)

28

42.
Most of the mass in an atom is made up of _____________________?
a)
protons and electrons
b)
protons and neutrons
c)
neutrons and electrons
d)
electrons and quarks
43.

Which subatomic particle determines the identity of an element? (how we tell which element is which)

a)

protons

b)

neutrons

c)

electrons

44.

Whose model suggested that negative particles were mixed in with positively charged material - like seeds in a watermelon?

a)

J.J. Thomson

b)

Ernest Rutherford

c)

Niels Bohr

d)

Albert Einstein

45.

Who discovered that the atom had an small, dense, positively charged center?

a)

Ernest Rutherford

b)

J.J Thomson

c)

Robert Millikan

d)

John Dalton

46.

Place the following atomic models in order, from earliest to latest:


A) Rutherford B) Thomson C) Dalton

a)

B, C, A

b)

C, A, B

c)

A, C, B

d)

C, B, A

47.
What can you conclude from the fact that scientists continue to update the atomic model?
a)
New information about atoms continues to be discovered
b)
Old information about atoms is completely useless
c)
Scientists did not have any information about atoms until a few years ago
d)
Scientists still have no idea what atoms look like
48.

Who named the positive center of the atom the "nucleus?"

a)

Democritus

b)

Dalton

c)

Thomson

d)

Rutherford

49.

Which scientists believed an atom was indivisible? (Choose all correct responses.)

a)

Democritus

b)

Dalton

c)

Thomson

d)

Rutherford

50.

Which scientist believed that elements differed from one another because their atoms had different mass?

a)

Democritus

b)

Dalton

c)

Thomson

d)

Rutherford

51.

In the atomic model nicknamed the "plum pudding" model, what do the plums represent?

a)

the nucleus

b)

the atom

c)

the electrons

d)

the positive material

52.

Which scientist proposed a new atomic model after discovering the electron in 1897?

a)

Dalton

b)

Thomson

c)

Rutherford

d)

Bohr

53.

Who discovered that atoms are mostly empty space?

a)

Dalton

b)

Thomson

c)

Rutherford

d)

Bohr

54.

In the model nicknamed "the solar system model" what are the electrons like?

a)

the sun

b)

the nucleus

c)

the planets

d)

the moon

55.

Who proposed that electrons move around the nucleus in circular orbits?

a)

Dalton

b)

Thomson

c)

Rutherford

d)

Bohr