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Thursday 2/27 - Chemical Reactions Review
By Elorde Tuliao
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Last updated 3 months ago
19 questions
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Did a Chemical Reaction Happen?
Chemical Reactions
1
0
Did a Chemical Reaction Happen?
Chemical Reaction
- Substances are mixed and at least
one new substance
with different properties (with
different molecules
) is formed.
Directions:
Analyze each diagram. Look carefully at both the
observable
scale
and the
nanoscale
.
Think about whether there is evidence that a chemical reaction happened.
Answer the question below each diagram.
Ice Melting:
1
1
Question 2
2.
Is this a chemical reaction? Explain why.
Chemical Reaction
- Substances are mixed and at least one
new substance
with different properties is formed.
Candles burn:
3
1
Question 4
4.
Is this a chemical reaction? Explain why.
Chemical Reaction
- Substances are mixed and at least one
new substance
with different properties is formed.
Baking Soda and Vinegar Mixing:
1
1
Question 6
6.
Is this a chemical reaction? Explain why.
Chemical Reaction
- Substances are mixed and at least one
new substance
with different properties is formed.
What Happens
Before
a Chemical Reaction?
Ca
+ 2H
2
O
→
Ca
(
O
H)
2
+ H
2
Before
After
1
Question 7
7.
How many Ca (calcium) atoms are there
before
the reaction?
1
Question 8
8.
How many O (oxygen) atoms are there
before
the reaction?
1
What Happens
After
a Chemical Reaction?
Ca
+ 2H
2
O
→
Ca
(
O
H)
2
+ H
2
Before
After
1
Question 10
10.
How many Ca (calcium) atoms are there
after
the reaction?
1
Question 11
11.
How many O (oxygen) atoms are there
after
the reaction?
1
Ca
+ 2H
2
O
→
Ca
(
O
H)
2
+ H
2
Before
After
1
Question 13
13.
What do you notice about the number of atoms before and after the chemical reaction?
1
1
1
1
Question 18
18.
The picture below is the
beginning
of a chemical reaction.
Choose the
correct model after chemical reaction
.
A)
B)
C)
D)
Question 19
19.
Explain why you chose that answer for 17.
Question 1
1.
Ice Melting:
Is there evidence of a chemical reaction?
A) Color change
B) Taste change
C) Temperature change
D) Gas is made
E) Electricity is made
F) Light is made
Question 3
3.
Candles burn:
Is there evidence of a chemical reaction?
Select all that apply.
A) Color change
B) Taste change
C) Temperature change
D) Gas is made
E) Electricity is made
F) Light is made
Question 5
5.
Baking Soda and Vinegar Mixing:
Is there evidence of a chemical reaction?
A) Color change
B) Taste change
C) Temperature change
D) Gas is made
E) Electricity is made
F) Light is made
Question 9
9.
How many H (hydrogen) atoms are there
before
the reaction?
Question 12
12.
How many H (hydrogen) atoms are there
after
the reaction?
Question 14
14.
Did any atoms created or destroyed (appear or disappear)?
Question 15
15.
Would the weight of the substances change before and after the chemical reaction?
Question 16
16.
What happens to the atoms and molecules before and after a chemical reaction?
Question 17
17.
Is this a chemical reaction? Explain why and explain what happened to the atoms.
Chemical Reaction
- Substances are mixed and at least one
new substance
with different properties is formed.