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Chemistry: Chemical Reactions & Organic Compounds

Total questions: 65

Worksheet time: 51mins

Name
Class
Date
1.

The chemical element of atomic number 6, a nonmetal which has two main forms (diamond and graphite) and which also occurs in impure form in charcoal, soot, and coal.

a)

Carbon

b)

Oxygen

c)

Element

d)

Nitrogen

2.

Organic compounds that are made of only hydrogen and carbon atoms. They are found in many places, including crude oil and natural gas.

a)

Hydrocarbons

b)

Nucleic Acids

c)

Proteins

d)

Lipids/Fats

3.

They are the most abundant compounds found in living organisms, including polysaccharides which are polymers composed of many sugar building blocks. They are used by cells to get and store energy.

a)

Polymers

b)

Organic Compound

c)

Carbohydrates

d)

Carbon

4.

Without these, cells could not live. Long chains of carbon and hydrogen molecules creating fatty acids.

a)

Carbohydrates

b)

Organic Chemistry

c)

Proteins

d)

Lipids

5.

These are required for the structure, function, and regulation of the body's cells, tissues and organs. They help build organelles and help defend against illness.

a)

Lipids

b)

Proteins

c)

Polymers

d)

Monomers

6.

1 of the 4 main categories of organic compounds. They are responsible for storing genetic information.

a)

Compounds

b)

Elements

c)

Nucleic Acids

d)

Polymers

7.

What is the smallest building block of matter?

a)

Compounds

b)

mixtures

c)

atoms

d)

pizza

8.

Which choice would be a molecule?

a)

O

b)

H

c)

Au

d)

H2

9.

Which of the following is a chemical change?

a)

A rusted can

b)

A crushed can

c)

A chopped piece of wood

d)

Water evaporating

10.
 The nucleus of an atom consists of protons and neutrons and the number of protons determines the element. 
a)
true
b)
false
11.
_______________ change is when a new substance is formed
a)
triangular
b)
chemical
c)
physical
d)
astral
12.
The left side of the equation below is called
a)
Products
b)
Reactants
13.
The right side of the equation below is called the
a)
products
b)
reactants
14.
A chemical change is different than a physical change because in a chemical change
a)
Chemicals are used
b)
Molecules do not physically touch
c)
A new substance is formed and in a physical change no new substance is formed
d)
The change can be seen but in a physical change it cannot
15.
Which statement is not a description of a chemical reaction?
a)
A solid is dropped into a beaker of liquid and a gas is released.
b)
Two liquids are mixed in a beaker and a solid forms at the bottom of the beaker.
c)
A solid is dropped into a beaker of liquid and an explosion occurs.
d)
A liquid is heated in the sun and half of it evaporates.
16.
A number in front of a chemical formula in an equation that indicates how many molecules or atoms of each reactant and product are involved in a reaction.
a)
Coefficient
b)
reactant
c)
subscript
d)
product 
17.
A chemical reaction that absorbs heat
a)
Single replacement
b)
Exothermic
c)
Endothermic
d)
Decomposition
18.
Which of the following is NOT a sign of a chemical reaction? 
a)
Color changes
b)
Cutting into fourths
c)
Light is produced
d)
Gas is formed
19.
Which of the following answers will balance the equation below?
__K + __Br2 --> __KBr
a)
2, 1, 1
b)
2, 3, 2
c)
2, 1, 2
d)
1, 2, 3
20.
What type of reaction is illustrated below?
2HI --> H2  +  I2
a)
synthesis
b)
decomposition
c)
single replacement
d)
double replacement
21.
a substance that is formed as the result of a chemical reaction
a)
Product 
b)
Reactant
c)
Starters
d)
Enders
22.

Why are chemical equations always balanced? Select ALL that apply.

a)

Matter cannot be created.

b)

Matter cannot be destroyed.

c)

Matter can only be rearranged/conserved.

d)

Matter doesn't matter.

23.
Which of the following is evidence of a chemical reaction?
a)
fizzing
b)
water changing to ice
c)
saltwater
d)
paper being cut in half
24.
What are Chemical Reactions?
a)
It's when you mix substances.
b)
a process in which atoms rearrange to form new substances
c)
When something bubbles.
d)
letter and numbers showing the types and number of atoms
25.
Which of the following is NOT evidence that that a chemical reaction has occurred?
a)
produces light/heat
b)
production of a gas
c)
formation of a precipitate
d)
melting
26.
The Law of Conservation of Mass states
a)
that matter exists in all states and reacts the same
b)
that matter can only be changed into new substances by introducing a catalyst
c)
that matter exists in the same state throughout any chemical change
d)
that matter cannot be created or destroyed and that the mass of the products must equal the mass of the reactants
27.
How many Al atoms are in this compound?         4Al2O3
a)
2
b)
8
c)
6
d)
4
28.
An gel ice pack getting cold after you put it in the freezer for an hour.
a)
Chemical Change
b)
Physical Change
29.
These are found on the Periodic Table.
a)
elements
b)
mixtures
c)
compounds
30.
The four organic compounds found in living things are?
a)
Carbohydrates, Lipids, Nucleic Acids, and Oxygen
b)
Carbohydrates, Lipids, Proteins, and Carbon
c)
Carbohydrates, Lipids, Proteins, Nucleic Acids
d)
Carbon, Lipids, Proteins, Nucleic Acids
31.
How many atoms of oxygen are there in water? H2O
a)
1
b)
2
c)
0
32.
Is burning a campfire a chemical or physical change?
a)
Chemical
b)
Physical 
33.

Starch is an example of a

A lipid

B nucleic acid

C protein

D carbohydrate

a)

carbohydrate

b)

lipid

c)

nucleic acid

d)

protein

34.

A runner is preparing for the Boston Marathon. She wants her dinner the night before to give her energy to complete the race. Which of the following will provide the maximum amount of energy ?

a)

a candy bar because of the sugar

b)

coffee because of the caffeine

c)

pasta because of the carbohydrates

d)

steak because of the protein

35.

Which organic molecule is found in the nucleus?

a)

carbohydrate

b)

lipid

c)

nucleic acid

d)

protein

36.

Which of the choices below best completes the following description of a compound? " A substance that is made up of ...."

a)

one kind of mixture

b)

one kind of element

c)

two or more elements

d)

two or more atoms combined

37.

Substances that can NOT be broken down chemically into substances are

a)

solutions

b)

mixtures

c)

elements

d)

compounds

38.

Fill-in-the-blank: ______________ are a combination of two or more atoms that are held together by a covalent bond

a)

elements

b)

ions

c)

metals

d)

molecules

39.

Which of the following results in a chemical reaction?

a)

boiling water

b)

bending a straw

c)

burning wood

d)

braiding hair

40.

Complete the sentence that describes how elements and compounds are similar? " Elements and compounds...."

a)

...can both be broken down by physical change

b)

...are both made up of different kinds of atoms

c)

... are both pure substances

d)

... are both listed on the periodic table

41.

Which of the following represents a chemical reaction?

a)

blowing dry wet hair

b)

slicing a loaf of bread into slices

c)

food coloring is dropped into water and water turns green

d)

in baking biscuits, the baking powder reacts to release carbon dioxide bubbles, The carbon dioxide cause the dough to rise

42.

One chemical property that can be measured in a substance is its reactivity with water. What is another chemical property?

a)

solubility

b)

malleability

c)

flammability

d)

density

43.

A beaker of ice and water is placed on a warm hot plate. Will ice undergo a physical or chemical change? Why?

a)

physical change, because it changes state

b)

physical change, because it forms a new substance

c)

chemical change, because it forms a new substance

d)

chemical change, because it changes state

44.

One example of changing a substance chemically is by

a)

painting it

b)

filtering it

c)

boiling it

d)

burning it

45.

A water molecule is made up of one Oxygen atom and two Hydrogen atoms. Why is water considered a pure substance?

a)

Water can be combined with other substances by physical means

b)

Water can be broken apart by physical means

c)

Water molecules are made up of different types of atoms

d)

Each water molecule is identical

46.

What type of substance is made up of a single type of atom?

a)

compound

b)

element

c)

mixture

d)

molecule

47.

Which of the following is an element?

a)

copper

b)

salt

c)

sugar

d)

water

48.

"In every chemical operation an equal quality of matter exists before and after the operation" is a statement of the law of

a)

Combining Volume

b)

Conservation of Mass

c)

Definite Proportions

d)

Multiple Proportions

49.

The atomic number of nitrogen is 7. The atomic mass is 14.01. This means that :

a)

A small percentage of nitrogen atoms have fewer than 7 neutrons

b)

A small percentage of nitrogen atoms have more than 7 neutrons

c)

some nitrogen atoms have fewer than 7 electrons

d)

all nitrogen atoms have exactly 7 neutrons

50.

What coefficients would balance the following equation?

Al + O2 = Al2O3

a)

4Al + 3O2 = 2Al2O3

b)

2Al + 3O2O3

c)

2Al + 3O2 = 1Al2O3

d)

3Al + 3O2 = 2Al2O3

51.

In a Lewis Dot diagram, the electrons shown:

a)

always equal the number of protons

b)

always add up to an even number

c)

are in the inner most energy level

d)

are in the outer most energy level

52.

In the process of ionic bonding

a)

atoms switch protons

b)

both atoms lose electrons

c)

both atoms gain electrons

d)

one atom gains one or more electrons and the other loses the same number

53.

Which coefficients would balance the following equation?

a)

2C2H6 + 10O2 --> 4CO2 + 6H2O

b)

2C2H6 + 7O2 --> 4CO2 + 6H2O

c)

2C2H6 + 5O2 --> 4CO2 + 6H2O

d)

1C2H6 + 5O2 --> 2CO2 + 3H2O

54.

________________ is not a greenhouse gas

a)

methane

b)

helium

c)

carbon dioxide

d)

water vapor

55.

What happens to the particles of a liquid as it becomes a gas?

a)

Particles start to slow down and stand still

b)

Particles condense to become closer and colder

c)

Particles bounce to create electrical light currents

d)

Particles spread further apart and begin to move faster and further apart.

56.

______The three main parts of the atoms include all EXCEPT

a)

photons that switch charges on valences

b)

protons that are positively charged in nucleus

c)

neutrons that are neutrally charged in nucleus

d)

electrons that are negatively charged on outer shell

57.

How is density calculated?

a)

Multiplying the electrons in the outside valances

b)

By dividing the mass by its volume of an object.

c)

Adding weight and height of an object

d)

Subtracting number of protons from atomic weight

58.

______What is the periodic table?

a)

a theory that atoms, molecules, & elements make great compounds

b)

a chart that rates the most popular elements

c)

chart of the elements showing the repeating pattern of their properties

d)

A graph of the density of substances

59.

Atmosphere is over 75% (percent) of this element

a)

Carbon

b)

Helium

c)

Hydrogen

d)

Nitrogen

60.

Where on the element chart square will you find the Atomic number ?

a)

By identifying the period row and family column it is in

b)

Must do math to figure out

c)

top of element square

d)

under the symbol of the element

61.

The ease with which an element combines with other elements and compounds is called

a)

thermal energy

b)

reactivity

c)

malleability

d)

James Bond effect

62.

What holds atoms together in molecules?

a)

thermal energy

b)

chemical bonds that are also known as ionic bonds that exchange electrons

c)

salt or sugar molecules

d)

James Bond effect

63.

You want to identify an element. How an you do so?

a)

How can you tell one element from another?

b)

by its color when changing state or cold

c)

by its shape when melting or boiling

d)

by specific physical and chemical properties

e)

by its texture and combining with other elements

64.

A coefficient in front of a molecule of a substance is the number of molecules of the reactant or product;

a number just below an element in a molecular formula indicates how many atoms of each element make up the molecule, and is called a(n) _____________.

a)

subscript

b)

symbol

c)

charged ion

d)

endothermic reaction

65.

What is the smallest building block of matter?

a)

Compounds

b)

mixtures

c)

atoms

d)

pizza