AnswersMO-Physical Science A-CRUnit Test

Describing Chemical Reactions Answers

0 verified answers
1
Free Preview

Leslie incorrectly balances an equation as 2C4H10 + 12O2 → 8CO2 + 10H2O.

A
2
B
8
C
10
D
12
2
Free Preview

Cecil writes the equation for the reaction of hydrogen and oxygen below.H2 + O2 → H2O

A
to show that most molecules exist in pairs
B
to show that most compounds exist in pairs
C
to show that atoms are conserved in chemical reactions
D
to show that atoms are created in chemical reactions
3

Liquid 1 reacts with Liquid 2, producing a solid and a gas. Using this scenario, which supports the law of conservation of mass?

A
mass of Liquid 1 + mass of solid = mass of Liquid 2 + mass of gas
B
mass of Liquid 1 – mass of solid = mass of Liquid 2 – mass of gas
C
mass of Liquid 1 – mass of Liquid 2 = mass of solid + mass of gas
D
mass of Liquid 1 + mass of Liquid 2 = mass of solid + mass of gas
4

The expression CaCO3 → CaO + CO2 is an example of a

A
reactant.
B
product.
C
chemical equation.
D
chemical progression.
5

Rust results from iron’s reaction to oxygen. An iron nail gains mass when it rusts. How does this reaction support the law of conservation of mass?

A
The mass of the rusted nail equals the mass of iron and the oxygen from the air it reacted with to form the rust.
B
The mass of the rusted nail increases because iron attracts more protons from the air.
C
The increased mass of the rusted nail is an exception to the law of conservation of mass since the rusted nail’s mass increases.
D
The increased mass of the rusted nail results from the rearrangement of protons and neutrons within oxygen, according to the law of conservation of mass.
6

What can the arrow in a chemical reaction be translated to mean? Check all that apply.

A
yields
B
accompanied by
C
react to form
D
added to
E
except
7

What is the number “4” in SiCl4?

A
a subscript
B
a coefficient
C
a product
D
a reactant
8

Franklin was performing an experiment by combining hydrochloric acid and sodium hydroxide. He measured the mass of his reactant materials to be 35g. The reaction resulted in the production of salt and water. He reported that his products weighed 32g.Which best describes the results of Franklin’s experiment?

A
No error occurred, some of the products are always lost as heat.
B
An error occurred, the mass of the reactants should equal the mass of the products.
C
An error occurred, the products should weigh more than the reactants.
D
No error occurred, water is not weighed when determining the weight of the products.
9

In a process called photosynthesis, plants use carbon dioxide and water, along with energy from sunlight, to produce sugar and oxygen. Photosynthesis is represented by the equation

Question illustration
A
6 molecules of CO2
B
6 molecules of H2O
C
18 molecules of CO2
D
24 molecules of H2O
10

Which is the correctly balanced equation for the reaction of rust, Fe2O3, and hydrochloric acid, HCl?

A
Fe2O3 + HCl → FeCl3 + H2O
B
Fe2O3 +3 HCl → 2 FeCl3 + H2O
C
Fe2O3 + 6 HCl → 2 FeCl3 + 3 H2O
D
Fe2O3 + 3 HCl → 2 FeCl3 + 3 H2O

Did you find these answers helpful?

More from this Course

Quiz
10 verified answers

Shifts in Equilibrium

Quiz
9 verified answers

Shifts in Equilibrium

Assignment
1 verified answers

Warm-Up