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Open Sci Ed Energy in Chemical Reactions

Total questions: 24

Worksheet time: 15mins

Name
Class
Date
1.

The substances present BEFORE a reaction occurs are called______.

a)

Products

b)

Exponents

c)

Factors

d)

Reactants

2.

What is the substance present at the END of a reaction called?

a)

Product

b)

Exponent

c)

Integer

d)

Reactant

3.

How do you know baking a cake is a chemical reaction?

a)

It tastes yummy.

b)

A new substance is formed.

c)

You mixed it together.

d)

It has ingredients.

4.

In EXOTHERMIC reactions, energy is _____ from the reaction to the surroundings.

a)

Absorbed

b)

Released

c)

Eliminated

d)

Evaporated

5.

In ENDOTHERMIC reactions, energy is _____ by the reaction system from the surroundings.

a)

Absorbed

b)

Released

c)

Eliminated

d)

Obliterated

6.

Temperature usually _____ in EXOthermic reactions.

a)

Stays the same

b)

Increases

c)

Decreases

7.

What usually happens to TEMPERATURE in an ENDOthermic reaction?

a)

Increases

b)

Decreases

c)

Stays the same

8.

Photosynthesis is an _____ reaction.

a)

EXOthermic

b)

ENDOthermic

9.

Cooking and baking are _____ reactions.

a)

EXOthermic

b)

ENDOthermic

10.

The starting temperature of a reaction was 21 degrees Celsius and the ending temperature was 44 degrees Celsius. What type of reaction occurred?

a)

EXOthermic

b)

ENDOthermic

11.

A chemist is doing an ENDOthermic reaction. The starting temperature was 25 degrees Celsius. Which of the following would be a reasonable ending temperature

a)

44 degrees

b)

30 degrees

c)

15 degrees

d)

25 degrees

12.

If a chemical reaction produces light or sound, it is likely a _____ reaction.

a)

EXOthermic

b)

ENDOthermic

13.
a substance formed when two or more elements are chemically bonded together
a)
Element Soup
b)
Pure Element
c)
Ion
d)
Compound
14.
What types of reactions absorb and release heat?
a)
acidic and basic
b)
endothermic and exothermic
c)
endothermic and heat transfusion
d)
covalent and ionic
15.
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
16.
A scientist combines chemicals and produces an exothermic reaction. What byproduct of this reaction would show that it is exothermic?
a)
heat
b)
coolness
c)
a precipitate
d)
gas bubbles
17.
In the reaction methane + oxygen turns into carbon dioxide + water, the methane and oxygen are called _______________.
a)
reactants
b)
products
c)
neutrals
d)
energizers
18.
What type of reaction is shown in the photo?
a)
Exothermic
b)
Isothermic
c)
Endothermic
d)
None of the  above
19.
How does an exothermic reaction feel?
a)
cold
b)
warm
c)
You can't feel it
d)
None of the above
20.
What tool is used to measure the amount of heat in a material?
a)
meter stick
b)
spring scale
c)
graduated cylinder
d)
thermometer
21.
What are the reactants in the chemical equation below?
Na+Cl2 →  2NaCl
a)
Na and Cl
b)
Na only
c)
NaCl
d)
2NaCl
22.
What are the products in the chemical equation pictured?
a)
CO2
b)
CO2 and H2O
c)
CHand O2
d)
O2
23.
How do you know that energy is being absorbed during a chemical reaction?
a)
Temperature increases
b)
Temperature decreases
24.
What type of reaction occurs in a hand warmer
a)
exothermic
b)
endothermic