Science Test

Evelyn is making a smoothie and she uses a variety of fruits and ingredients. What is the main difference between the smoothie she makes and a pure substance like distilled water?

• Pure substances have a variable composition, mixtures do not

• Mixtures have a fixed composition, pure substances do not

• Pure substances have a fixed composition, mixtures do not

• Mixtures are made of one type of atom, pure substances are not

Abigail is conducting an experiment in her science class. She wants to know what is the smallest unit a material can be divided into without changing its properties. What should she consider?

• Atom

• Molecule

• Cell

• Compound

During a science class, Henry was asked to identify a molecule that is composed of three oxygen atoms. Which molecule should he choose?

• O2

• O3

• CO2

• H2O

Liam is making a fruit salad. Which of the following is NOT a characteristic of the fruit salad mixture?

• Not a pure substance

• Chemically combined

• Samples vary from different areas

• Doesn't change properties of separate parts

Abigail is conducting a science experiment in her chemistry class. She writes a chemical equation on the board. What is the significance of the arrow in the chemical equation?

• It shows the direction of the reaction.

• It indicates the speed of the reaction.

• It shows the temperature of the reaction.

• It indicates the pressure of the reaction.

Mia is making ice cubes from water. What kind of change is this?

• A change that creates a new substance

• A change that alters the form or appearance of a substance

• A change that involves a chemical reaction

• A change that cannot be reversed

What is an example of a physical change involving water?

• Freezing water

• Electrolysis of water

• Mixing water with acid

• Water reacting with sodium

When Ava places an ice cube in a glass of water and it melts, what type of change is occurring?

• A change in the state of matter

• A change in chemical composition

• A change in atomic structure

• A change in molecular bonds

Lily took an ice cube from the freezer. What is the state of matter of the ice cube?

• Gas

• Liquid

• Solid

• Plasma

Aria is observing different changes in her surroundings. She notices that some changes are physical. What is NOT a result of a physical change?

• Change in texture

• Change in shape

• Change in chemical properties

• Change in color