Unit 4 Practice Test

In a chemical equation, is it true that -

• the reactant side and product side can have different numbers of atoms for each element
• there can be different elements on the reactant side and the product side
• an element or compound must be accompanied by a phase change
• the coefficients indicate the number of molecules of each reactant used and the number of molecules of each product made

Tags

NGSS.HS-PS1-7

Which of the following models best demonstrates a balanced chemical equation?

• F
• G
• H
• J

Tags

NGSS.HS-PS1-7

The formula below represents the most common carbohydrate known as glucose. Which information can be determined from the chemical formula?
C₆H₁₂O₆

• The structural arrangement of the atoms in a glucose molecule
• The color of a glucose molecule
• The size of a glucose molecule
• The number of atoms of each element in a glucose molecule

Tags

NGSS.MS-PS1-1

Two clear colorless solutions were combined.
The student observed that the temperature changed from 25 •C to 23 •C when the solutions were combined and that a white substance rapidly formed and settled to the bottom of the container. What most likely happened to produce these results?

• One of the original compounds came out of solution
• The solutions reacted chemically
• Some of the water froze into ice crystals
• Rapid evaporation of water occurred, leaving a solid

Tags

NGSS.HS-PS1-4

NGSS.HS-PS1-5

NGSS.HS-PS3-4

The Law of Conservation of Mass states

• that matter exists in all states and reacts the same

• that matter can only be changed into new substances by introducing a catalyst

• that matter exists in the same state throughout any chemical change

• that matter cannot be created or destroyed and that the mass of the products must equal the mass of the reactants

Tags

NGSS.HS-PS1-7

Identify this type of reaction,
Cl₂ + 2KI _-->  I₂ + 2KCl

• Synthesis
• Single displacement
• Double displacement
• Decomposition

2 C₅H₅ + Fe --> Fe(C₅H₅)₂ 

• single displacement
• double displacement
• decomposition
• synthesis

2 RbNO₃ + BeF₂ --> Be(NO₃)₂ + 2 RbF

• single replacement (displacment)

• double replacement (displacment)

• decomposition

• synthesis

Mg + N₂ →Mg₃N₂

• Synthesis (combination)
• Decomposition
• Single replacement
• Combustion

In a chemical reaction

• products form reactants

• new substances are formed

• the law of conservation of mass applies

• all of the above are true

• 2 of the above are true