8th grade science Chapter 2

What is a heterogeneous mixture?

• A mixture with uniform composition

• A mixture with distinct, visible components

• A mixture of gases only
  
  

• A chemically bonded mixture

Which method is best to separate sand and iron filings?

• Filtration

• Using a magnet

• Evaporation

• Dissolving in water

In a solution, the solvent is:

• The substance being dissolved

• The substance that dissolves the solute
  
  

• A gas only

• The substance forming a precipitate

What happens to the solubility of sugar in water when temperatures increases?

• It decreases

• It stays the same

• It Increases

• It depends on the pressure

Tags

NGSS.MS-PS1-4

What is an example of a physical change?

• Baking a cake

• Rusting iron

• Melting ice

• Burning wood

Tags

NGSS.MS-PS1-4

Which of the following is NOT evidence of a chemical reaction?

• Melting

• Color change

• Gas production

• Formation of a precipitate

Tags

NGSS.MS-PS1-2

What type of reaction releases heat?

• Endothermic

• Exothermic

• Neutralization

• Physical Reaction

Which factor does NOT increase the rate of a chemical reaction?

• Increased surface area

• Higher temperature

• Using a catalyst

• Decreasing reactant concentration

Tags

NGSS.HS-PS1-5

A reaction requiring heat to occur is called:

• Exothermic

• Endothermic

• Combustion

• Decomposition

Tags

NGSS.MS-PS1-4

What is the role of a catalyst in a reaction?

• Lowers the activation energy

• Slows down the reaction

• Changes the products

• Increases temperature