Unit 2 Review

The substance that is formed after a chemical reaction is called the ________.

• Reactants

• Products

• Heat

• Chemicals

Tags

NGSS.MS-PS1-2

One of the signs of a chemical reaction taking place is ____________.

• bubbles are produced

• shape is changing

• products are not forming

• reactants are not combining

Tags

NGSS.MS-PS1-2

What is a pure substance made of two or more elements that are chemically combined?

• Element

• Compound

• Mixture

• Solution

Mixtures are two or more substances that are not chemically combined. Which of the following statements is true about the mixture?

• Pepsi is a heterogeneous mixture.

• Milk is a pure substance, not a mixture.

• Cranberry juice is a homogeneous mixture.

• Oatmeal with raisins is a homogeneous mixture.

A physical change is ____________.

• Where the substance or substances modified but a new substance is not formed.

• Where two substances react to become something with new properties.

• When you mix two substances together and it changes color.

• When a substance or substances are rearranged to produce a new substance.

Alisa needs to make some hot tea for her ill mother. She uses some ice-cold water from the freezer and heats it in the kettle. As she hears the teapot whistling, she asks herself, "How is the motion of the ice water's particles changing as the hot tea is being made?" What is the best answer to Alisa's question?

• The particles in the cold water moved at the same rate until an increase in temperature caused a decrease in particle motion in the hot tea.

• The particles in the cold water moved at a slow rate until a decrease in temperature caused an increase in particle motion in the hot tea.

• The particles in the cold water moved at a slow rate until an increase in temperature caused an increase in particle motion in the hot tea.

• The particles in the cold water moved at a high rate until an increase in temperature caused a decrease in particle motion in the hot tea.

Tags

NGSS.MS-PS1-4

NGSS.MS-PS3-4

Melting, sublimation, evaporation & condensation are examples of

• A chemical change

• A physical change

• Exothermic reaction

• Endothermic reaction

Tags

NGSS.MS-PS1-4

NGSS.MS-PS3-4

Which of the following is not true about gases?

• They spread out to fill their containers.

• The particles move very quickly.

• The particles move very slowly.

• They have an indefinite volume.

When magnesium is ignited it produces a great amount of light. This is an example of an (a) ____________.

• Exothermic chemical reaction

• Endothermic chemical reaction

• Exothermic physical change

• Phase change

Tags

NGSS.MS-PS1-2

You are given a mystery object in science class. Your teacher asks you to determine if your object is denser than water. You place the object in water, and it sinks. What statement would best describe this situation?

• Water is denser than the mystery substance.

• They both have the same mass.

• The mystery substance must be hollow.

• The mystery substance is denser than water.