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Molecules, compounds and mixtures Review

Total questions: 80

Worksheet time: 2hrs 2mins

Name
Class
Date
1.

The chart below lists some substances and their symbols. How many of these substances are examples of elements?

a)

1

b)

2

c)

3

d)

4

2.

What makes elements and compounds different from mixtures? Elements & compounds-

a)

have a constant composition (pure substances)

b)

are made of gases

c)

Will not change when heated

d)

conduct electric current

3.

What is the relationship between molecules and atoms?

a)

Molecules are combinations of two or more atoms.

b)

Molecules are the parts that make up atoms

c)

Molecules are the gaseous parts of atoms

d)

Molecules are atoms that have a positive charge

4.

In the diagrams provided, the circles of different colors represent the atoms of different elements. Which diagram represents a mixture?

a)

I

b)

II

c)

III

d)

IV

5.

Sam's mother is cooking breakfast in a cast-iron frying pan. If the pan is made only of iron, what can Sam conclude?

a)

The pan is a pure substance with the chemical symbol Ir.

b)

The pan is a pure substance with the chemical symbol I.

c)

The pan is a pure substance with the chemical symbol F.

d)

The pan is a pure substance with the chemical symbol Fe.

6.
How many elements are represented in the compound?
Na2CO3
a)
1
b)
2
c)
3
d)
4
7.
A combination of substances that are not chemically combined is called a(n)____________. 
a)
mixture
b)
compound
c)
physical
8.
An element is made up of only one kind of _____.
a)
isotope
b)
plastic
c)
atom
d)
metal
9.
The blue numbers in the image below are called ___________.
a)
compounds
b)
coefficients
c)
subscripts
d)
chemical formulas
10.
What is H2SO4 
 made up of?
a)
2 hydrogen, 1 sulfur, 4 oxygen
b)
1 hydrogen, 2 sulfur, 4 oxygen
c)
2 hydrogen & 4 sodium
d)
1 hydrogen & 6 sodium
11.
Water is a ___________. 
a)
element 
b)
mixture 
c)
compound 
12.

In this diagram, Y represents...

a)

An element

b)

A molecule

c)

A compound

d)

A mixture

13.

Which example is a compound?

a)

N2

b)

O2

c)

Cu

d)

H2O2

14.

Which of the following is a pure substance?

a)

Orange Juice

b)

Lucky Charms Cereal

c)

Gold (Au)

d)

Granola and Yogurt Parfait

15.

Salt has the chemical formula NaCl because it is made up of atoms of Sodium (Na) and Chlorine (Cl). Which statement most accurately describes this compound in relation to the elements it is made of?

a)

When sodium and chlorine chemically combine, they create a substance with completely different properties

b)

Salt has similar properties to the sodium and chlorine it is made of

c)

Once salt is formed the sodium and chlorine atoms no longer exist, only salt atoms

d)

Salt can easily be separated back into sodium and chlorine atoms through physical means

16.

Which of the following statements is true?

a)

All molecules are compounds but not all compounds are molecules

b)

All compounds are molecules but not all molecules are compounds

c)

All elements exist as molecules

d)

Any time two atoms combine a compound is formed

17.

This is a picture of

a)

Compound

b)

Elements

c)

Heterogenous solution

d)

Pure substance

18.

This is a picture of

a)

Mixture

b)

Solution

c)

Compound

d)

Element

19.

This is an example of

a)

Solution

b)

Pure Substance

c)

Molecule

d)

Element

20.

Salad dressing, gelatin, whipped cream, and apple juice were served at a dinner at Kim's house. Each of the items is a mixture. Which of the mixtures is a heterogeneous mixture?

a)

Salad dressing

b)

whipped cream

c)

gelatin

d)

apple juice

21.

Pure Substance or Mixture?

made from one type of atom

a)

pure substance

b)

mixture

22.
Sweet Tea
a)
Element
b)
Compound
c)
Homogeneous Mixture
d)
Heterogeneous Mixture
23.
NaCl
a)
Element
b)
Compound
c)
Homogeneous Mixture
d)
Heterogeneous Mixture
24.
Aluminum
a)
Element
b)
Compound
c)
Homogeneous Mixture
d)
Heterogeneous Mixture
25.
Carbon
a)
Element
b)
Compound
c)
Homogeneous Mixture
d)
Heterogeneous Mixture
26.
Kool-Aid
a)
Element
b)
Compound
c)
Homogeneous Mixture
d)
Heterogeneous Mixture
27.
Chicken soup is an example of what kind of substance?
a)
homogenous mixture
b)
solution
c)
heterogeneous mixture
d)
compound
28.
Italian Salad Dressing is a . . .
a)
heterogeneous mixture
b)
homogeneous mixture
c)
Pure Substance
d)
Compound
29.
What type of mixture is this?
a)
homogenous mixture
b)
chemical
c)
heterogeneous mixture 
d)
solid mix
30.
A mixture that is NOT evenly distributed is called ....
a)
Compounded
b)
Homogenous
c)
Heterogenous
d)
Salty
31.
Air
a)
Heterogeneous
b)
Homogeneous
32.

What kind of mixture is shown in the picture?

a)

Homogeneous

b)

Heterogeneous

33.

What kind of mixture is shown in the picture?

a)

Homogeneous

b)

Heterogeneous

34.

Which of the following is true of oxygen?

a)

Oxygen is an element because its most basic unit is a single type of atom

b)

Oxygen is a compound because its most basic unit is a single type of atom.

c)

Oxygen is a mixture because its most basic unit contains more than one particle.

d)

Oxygen is a compound because its most basic unit contains more than one type of particle.

35.

Humans absorb oxygen from the air they breathe in and exhale carbon dioxide gas, CO2. Carbon dioxide gas is

a)

an element made of carbon and oxygen atoms.

b)

a solution made of carbon and oxygen atoms.

c)

a compound of carbon and oxygen atoms.

d)

a mixture of carbon and oxygen atoms.

36.

Elements

a)

are made of two or more types of atoms chemically bonded together

b)

are made of one type of atom

c)

are made of two or more types of molecules combined in the same space

d)

are always individual atoms

37.

Mixtures

a)

are made of two different types of atoms chemically bonded together

b)

Are only liquids

c)

Cannot be separated

d)

Can be separated using physical properties

38.

Which of the following are examples of Compounds?

a)

Salt

b)

Salt Water

c)

N2 + O2

d)

C6H12O6

e)

Co

39.

What can be inferred from the picture?

a)

Elements are always made of individual atoms

b)

Mixtures contain only one type of molecule

c)

Molecules always make compounds

d)

Compounds are pure substances

40.

The table lists the chemical formulas or symbols of a few common substances. Which two substances are compounds?

a)

aluminum and iron

b)

iron and sodium chloride

c)

carbon dioxide and aluminum

d)

sodium chloride and carbon dioxide

41.

How many atoms of Hydrogen are in H2O

a)

1

b)

2

c)

3

d)

more than 3

42.

How many different elements are present in H2COCH2

a)

5

b)

4

c)

3

d)

2

43.

Calculate the number of Oxygen atoms in Al(OH)3

a)

1

b)

2

c)

3

d)

4

44.

The ______ are numbers found on the lower right-hand side of an element symbol.

a)

Coefficient

b)

Exponent

c)

Multiplier

d)

Subscript

45.

Hydrogen and oxygen combine to form water, as shown in the diagram below. Based on the diagram, which statement best represents the formation of water from hydrogen and oxygen?

a)

A mixture has formed from hydrogen and oxygen physically combined.

b)

A mixture has formed from hydrogen and oxygen chemically combined.

c)

A pure substance has formed from the hydrogen and oxygen physically combining.

d)

A pure substance has formed from the hydrogen and oxygen chemically combining.

46.

Ms. Roberts asked Tim to put the label 'compound' on the correct jar in the picture. Which of the four substances is a compound?

a)

chlorine

b)

nitrogen

c)

sodium

d)

water

47.

The picture below represents which type of substance?

a)

Element

b)

Compound

c)

Mixture of elements

d)

Mixture of compounds

e)

Mixture of elements and compounds

48.

Based on the diagram, identify the type of substance represented.

a)

Element

b)

Compound

c)

Mixture of elements

d)

Mixture of compounds

e)

Mixture of elements and compounds

49.

What is this?

salt (NaCl)

a)

Pure Substance

b)

mixture

50.

Each ball shown in the diagram represents a type of atom. Balls of the same shade and size represent the same kind of atom. Which diagram shows a mixture?

a)

1

b)

2

c)

3

d)

4

51.

The image shows the atomic arrangements of four different substances. Which are compounds and why?

a)

hydrogen because it contains only one kind of atom

b)

methane because it contains the maximum number of molecules

c)

water and carbon dioxide because each contains a similar number of molecules

d)

water, carbon dioxide, and methane because each contains more than one element

52.

Which term refers to matter that could be heterogeneous?

a)

compound

b)

element

c)

mixture

d)

solution

53.

Mixtures

a)

are made of two different types of atoms chemically bonded together

b)

Are only liquids

c)

Cannot be separated

d)

Can be separated using physical properties

54.

Which is the smallest particle of an element that has the same properties as that element?

a)

atom

b)

molecule

c)

electron

d)

neutron

55.

Which of the following are examples of Compounds?

a)

Salt

b)

Salt Water

c)

N2 + O2

d)

C6H12O6

e)

Co

56.

What can be inferred from the picture?

a)

Elements are always made of individual atoms

b)

Mixtures contain only one type of molecule

c)

Molecules always make compounds

d)

Compounds are pure substances

57.

When two or more substances combine, but each keeps its own properties, the new combination is called a(an)

a)

element

b)

compound

c)

mixture

d)

heterogenous mixture

e)

homogeneous mixture

58.

A substance made from one type of atom. It cannot be changed into anything simpler

a)

element

b)

compound

c)

mixture

59.

This substance represents....

a)

an atom

b)

a compound

c)

a mixture

d)

a molecule

60.

This substance represents

a)

a mixture of elements

b)

elements

c)

a mixture of molecules

d)

compounds

61.

Which type of mixture is represented in this image?

(Think: Are the particles spread out evenly throughout, or are the particles chunked together?)

a)

Compound mixture

b)

Heterogeneous mixture

c)

Homogeneous mixture

d)

Elemental mixture

62.

Which type of mixture is represented in this image?

(Think: Are the particles spread out evenly throughout, or are the particles chunked together?)

a)

Homogeneous mixture

b)

Elemental mixture

c)

Heterogeneous mixture

d)

Compound mixture

63.

Which is an example of a heterogenous mixture?

a)

Lucky Charms cereal

b)

cranberry juice

c)

brass metal

d)

salt dissolved in water

64.

Which is an example of a homogenous mixture?

a)

Lucky Charms cereal

b)

salt dissolved in water

c)

orange juice with LOTS of pulp

d)

trail mix

65.

A mixture with parts that are evenly and thoroughly distributed is

a)

suspension

b)

Heterogeneous mixture

c)

Homogeneous mixture

d)

All mixtures have evenly mixed parts

66.

What type of mixture is this?

a)

Homogeneous

b)

Heterogeneous

67.

What type of mixture is this?

a)

Homogeneous

b)

Heterogeneous

68.

What type of mixture is this?

a)

Homogeneous

b)

Heterogeneous

69.
This type of mixture contains two or more substances that are visibly distinguishable. 
a)
homogeneous
b)
heterogeneous
c)
solution
d)
colloid
70.
A homogeneous mixture
a)
Is not uniform 
b)
Is uniform 
71.
Cookies and cream ice cream would be classified as
a)
A homogenous mixture
b)
A heterogenous mixture
c)
An element
d)
A compound
72.

When two or more elements combine chemically, they form _________.

a)

DNA

b)

atoms

c)

molecules

d)

compounds

73.

The chemical formula for artificial sweetener is

C7H5NO3SC_7H_5NO_3S  How many different elements are in the artificial sweetener?

a)

17

b)

5

c)

15

d)

4

74.

Which of the following is a compound?

a)

He

b)

CO

c)

Si

d)

Co

75.

One way to tell how many elements a compound has is to..

a)

multiply the number

b)

count the capital letters

c)

add up all the numbers

d)

count the letters

76.
How many elements are represented in the compound?
Na2CO3
a)
1
b)
2
c)
3
d)
4
77.

Which of the following items is NOT a compound?

a)

baking soda

b)

salad dressing

c)

surcrose

d)

water

78.

Which particle diagram contains only one compound?

a)

A

b)

B

c)

C

d)

D

79.

Kiera was eating a snack made of peanuts, raisins, and chocolate chips. Every handful she gets may be a little different from the one before. Which term best describes this snack?

a)

a compound

b)

an element

c)

a heterogeneous mixture

d)

a homogeneous mixture (solution)

80.

Milk is a ________

a)

compound

b)

homogeneous mixture

c)

element

d)

heterogeneous mixture

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