WorksheetsChemical Reactions Review
Total questions: 16
Worksheet time: 33mins
Name
Class
Date
1.
True or False: In a complete chemical equation, there must be the same number of atoms of each element on the reactants and products side.
a)
True
b)
False
2.
In a chemical reaction, atoms (a) and form new bonds.
3.
Look at the chemical equation.
How many atoms of mercury (Hg) are in the reactants?
(a)
4.
Look at the chemical equation.
How many atoms of nitrogen (N) are in the reactants?
(a)
5.
Look at the chemical equation.
How many atoms of oxygen (O) are in the products?
(a)
6.
What is the arrow in a chemical equation...
H2 + O --> H2O
H2 + O --> H2O
a)
Reactants
b)
Products
c)
Yields
d)
Chemical Equation
7.
The substances at the beginning of a chemical equation are called the ____
a)
product
b)
yield
c)
chemical symbol
d)
reactants
8.
In the equation, 2Mg + O2 ---> 2MgO, which are the reactants?
a)
Mg and O
b)
MgO
c)
Mg and MgO
d)
O and MgO
9.
In a chemical reaction, everything to the right of the arrow is called ______________.
a)
Products
b)
Yields
c)
Molecules
d)
Reactants
10.
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
11.
Which of the following models best demonstrates a balanced chemical equation?
a)
F
b)
G
c)
H
d)
J
12.
Coal contains carbon and other elements. Carbon dioxide forms when coal burns in the presence of oxygen. Which of these is the best evidence that a chemical reaction occurs when coal burns?
a)
The shape of the coal changes
b)
Oxygen is present
c)
A new substance is produced
d)
Coal is made up of more than one element
13.
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
14.
A different chemical substance is formed when _____.
a)
water boils
b)
metal rusts
c)
ice melts
d)
rock is crushed
15.
• During a chemical reaction, atoms cannot be ________ or ___________.
a)
Changed or rearranged
b)
Created or destroyed
c)
Monitored or observed
d)
Tested or filtered
16.
Digesting your food is an example of
a)
chemical change
b)
physical change
100 %
