WorksheetsChemical Reactions
Total questions: 61
Worksheet time: 2hrs 4mins
Name
Class
Date
1.
The reactants are on the left side of the chemical equation.
a)
True
b)
False
2.
In which of these compounds are there twice as many oxygen atoms as hydrogen atoms?
a)
H3PO4
b)
H2SO4
c)
HCIO3
d)
H20
3.
Which chemical equation is balanced?
a)
Na + O2 --> Na2O
b)
2Na2 + O2 --> 2Na2O
c)
2Na + 2O2 --> 2Na2O
d)
2Na + O2 --> 2Na2O
4.
What type of reaction involves the breaking down of a substance into simpler substances?
a)
Single Displacement Reaction
b)
Double Displacement Reaction
c)
Synthesis Reaction
d)
Decomposition Reaction
5.
What type of reaction involves 2 substances combining to form 1 new compound?
a)
Decomposition Reaction
b)
Single Displacement Reaction
c)
Double Displacement Reaction
d)
Synthesis Reaction
6.
What type of reaction involves one element replacing another element in a compound?
a)
Single Displacement Reaction
b)
Double Displacement Reaction
c)
Synthesis Reaction
d)
Decomposition Reaction
7.
What type of reaction involves ions from 2 compounds exchanging places to form 2 completely new compounds?
a)
Single Displacement Reaction
b)
Double Displacement Reaction
c)
Synthesis Reaction
d)
Decomposition Reaction
8.
Which of the following is NOT an example of a chemical reaction?
a)
Wood Burning
b)
A cake baking in an oven
c)
Melting Ice Cream
d)
Mixing Vinegar and Baking Soda
9.
What are the reactants in the chemical equation pictured?
a)
CH4 and CO2
b)
CH4 and O2
c)
CO2 and H2O
d)
O2 and H2O
10.
What are the products of the chemical reaction pictured?
a)
CH4 and CO2
b)
CH4 and O2
c)
CO2 and H2O
d)
O2 and H2O
11.
What is the large number written before a chemical formula called?
a)
Coefficient
b)
Subscript
c)
Reactant
d)
Product
12.
What is the small number written after a chemical symbol called?
a)
Coefficient
b)
Subscript
c)
Product
d)
Reactant
13.
What is a shorthand notation that represents a compound or molecule called?
a)
Chemical Equation
b)
Chemical Formula
c)
Chemical Reaction
d)
Chemical
14.
According to the law of conservation of mass...
a)
sometimes atoms are lost
b)
sometimes atoms are gained
c)
atoms are never lost nor gained
d)
atoms are lost and gained
15.
In an exothermic reaction energy is ...
a)
released
b)
absorbed
c)
protons
d)
electrons
16.
In an endothermic reaction energy is...
a)
released
b)
absorbed
c)
protons
d)
neutrons
17.
When a scientist mixed two chemicals, an exothermic reaction takes place. Which of the following would be proof that the reaction was exothermic?
a)
a change of color
b)
a change of state
c)
a temperature decrease
d)
a temperature increase
18.
Which of the following is a chemical change?
a)
water freezes to form ice
b)
sugar dissolves in water
c)
gasoline burns in a car engine
d)
a piece of metal expands when it is heated
19.
In the reaction methane + oxygen turns into carbon dioxide + water, the methane and oxygen are called _______________.
a)
reactants
b)
products
c)
neutrals
d)
energizers
20.
A change in the shape of an object is an example of _________________.
a)
a chemical change
b)
energy
c)
an endothermic change
d)
a physical change
21.
What type of change occurs when a new substance is formed that has different properties from the original substances?
a)
chemical change
b)
nuclear change
c)
physical change
d)
mutation
22.
Which of the following is an example of a physical change?
a)
souring milk
b)
mixing baking soda and vinegar
c)
rusting metal
d)
mixing oil and vinegar
23.
Which of the following is a chemical change?
a)
the rusting of iron
b)
dissolving salt in water
c)
melting an ice cube
d)
bending a copper wire
24.
Which of the following is an example of a chemical change?
a)
rusting of a bicycle
b)
painting a house
c)
washing a dog
d)
tearing up a newspaper
25.
If you combine two substances in a beaker at room temperature and the beaker feels cold to the touch, it means that the substances:
a)
have not reacted with each other
b)
have undergone an endothermic reaction
c)
have undergone a physical change
d)
have undergone an exothermic reaction
26.
Which of the following is an example of a physical change?
a)
wood burning
b)
ice melting
c)
food digesting
d)
iron rusting
27.
In any chemical reaction, the mass of the products is always:
a)
slightly less than the mass of the reactants
b)
much less than the mass of the reactants
c)
the same as the mass of the reactants
d)
greater than the mass of the reactants
28.
Your mother used pancake mix, eggs, and milk to make pancakes. Which of these is the product?
a)
the pancake mix
b)
the eggs
c)
the milk
d)
the pancakes
29.
This is used to represent the number of each atom being represented.
a)
An exponent
b)
The coefficient
c)
A molecule
d)
The subscript
30.
This appears on the left side of a chemical formula, and represents how many molecules there are.
a)
An Atom
b)
The Subscript
c)
A Molecule
d)
The Coefficient
31.
How many hydrogen atoms are in this chemical formula:
a)
4 hydrogen atoms
b)
1 hydrogen atom
c)
2 hydrogen atoms
d)
3 hydrogen atoms
32.
How many oxygen atoms are in this chemical formula?
a)
7 oxygen atoms
b)
4 oxygen atoms
c)
3 oxygen atoms
d)
1 oxygen atoms
33.
How many oxygen atoms are in this chemical formula?
a)
6 oxygen atoms
b)
2 oxygen atoms
c)
3 oxygen atoms
d)
4 oxygen atoms
34.
How many elements are in C6H12O6?
a)
24
b)
432
c)
3
d)
1
35.
A physical change is?
a)
It changes the object into something different
b)
Objects or substances undergo a change that does not change their chemical composition
c)
it is just like a chemical reaction
d)
Paper burning
36.
A chemical change is?
a)
a shoe lace cut in half
b)
doesn't change anything
c)
changes the look of an object
d)
change that results in the formation of new chemical substances
37.
What is the left part of a chemical equation called?
H2 + O → H2O
H2 + O → H2O
a)
Reactants
b)
Products
c)
Yields
d)
Chemical Equation
38.
What is the right part of a chemical equation called?
H2 + O → H2O
H2 + O → H2O
a)
Reactants
b)
Products
c)
Yields
d)
Chemical Equation
39.
Is this balanced?
2HgO → 2Hg + O2
2HgO → 2Hg + O2
a)
Yes
b)
No
40.
Is this balanced?
Al + O2 → 2Al2O3
Al + O2 → 2Al2O3
a)
Yes
b)
No
41.
One of the signs of a chemical reaction taking place is:
a)
Bubbles are produced in the reacting vessel
b)
Reactants are not combining
c)
Products are not forming
d)
Colour is not changing
42.
Why must chemical equations be balanced?
a)
So that the equation doesn't explode
b)
The reaction won't happen until it is balanced
c)
Matter cannot be created or destroyed
d)
None of these
43.
The arrow symbol used in a chemical equation
a)
Yield sign
b)
Subscript
c)
Coefficient
d)
Chemical formula
44.
Why is the following chemical equation not balanced?
H2 + O2 --> H2O
H2 + O2 --> H2O
a)
each side of the equation has a different number of oxygen atoms
b)
each side of the equation has a different number of hydrogen atoms
c)
each side has the same mass
45.
At the end of chemical reactions, what is the total mass of the reactants compared to the total mass of the products?
a)
the product is doubled
b)
the product is half the mass of the reactants
c)
the mass is the same
d)
the mass changes depending on the reaction
46.
What coefficient should be used to make the following equation balanced?
N2+O2--> _NO
N2+O2--> _NO
a)
1
b)
2
c)
3
d)
4
47.
Is this chemical equation balanced or unbalanced?
a)
Balanced
b)
Unbalanced
48.
A combination of chemical symbols to represent a substance is a:
a)
chemical formula
b)
chemical bond
c)
chemical reaction
d)
chemical equation
49.
In the equation,
2Mg + O2 → 2MgO,
which are the reactants?
2Mg + O2 → 2MgO,
which are the reactants?
a)
Mg and O2
b)
MgO
c)
Mg and MgO
d)
O2 and MgO
50.
What type of reaction is this?
2Mg + O2 → 2MgO
2Mg + O2 → 2MgO
a)
Synthesis
b)
Single Replacement
c)
Double Replacement
d)
Decomposition
51.
Si + S8 --> Si2S4
a)
Synthesis (combination)
b)
Decomposition
c)
Single replacement
d)
Double replacement
52.
Ca + AlCl3 --> CaCl2 + Al
a)
Synthesis (combination)
b)
Decomposition
c)
Single replacement
d)
Double replacement
53.
KOH + H3PO4 --> K3PO4 + H2O
a)
Synthesis (combination)
b)
Decomposition
c)
Single replacement
d)
Double replacement
54.
Mg + N2 --> Mg3N2
a)
Synthesis (combination)
b)
Decomposition
c)
Single replacement
d)
Combustion
55.
NO2 --> N2 + O2
a)
Synthesis (combination)
b)
Decomposition
c)
Single replacement
d)
Combustion
56.
AB + CD = AD + CB
a)
Double Replacement
b)
Single Replacement
c)
Combustion
d)
Decomposition
57.
A + BC = B + AC
a)
Single Replacement
b)
Combustion
c)
Double Replacement
d)
Synthesis
58.
AB = A + B
a)
Decomposition
b)
Single Replacement
c)
Combustion
d)
Synthesis
59.
A chemical reaction absorbs energy in the form of heat is called
a)
Endothermic
b)
Exothermic
c)
Combustion
d)
Unbalanced
60.
Which chemical reaction breaks down into 2 substances?
a)
Double Replacement
b)
Single Replacement
c)
Synthesis
d)
Decomposition
61.
Which chemical reaction takes place when 2 substances react to form a single product?
a)
Decomposition
b)
Double Replacement
c)
Single Replacement
d)
Synthesis
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