Science CA #2 Review

Which statement describes a difference between static electricity and electric current?

• A. Only electric current involves energy.

• B. Only electric current involves the movement of electrons

• C. Only static electricity involves sudden electric discharges.

• D. Only static electricity involves negative and positive charges.

What happens when a mixture is separated?

• A. A substance is lost.

• B. A new substance is formed.

• C. The substances stay the same.

• D. The mass of the substances changes.

Which of these will the south pole of a bar magnet repel?

• A. a paper clip

• B. an iron nail

• C. the north pole of another magnet.

• D. the south pole of another magnet.

A puddle of water on a sidewalk evaporated. Which statement could explain what happened?

• A. The temperature fell below 0 degrees C, making the water freeze.

• B. The temperature fell below 0 degrees C, making the water turn into vapor.

• C. The sun heated the water, which changed from a liquid to a gas.

• D. The sun heated the water, which changed from a liquid to a solid.

A student replaces the switch in an electric circuit with an object. A light bulb in the circuit does not light up. What can the student conclude about the object?

• A. It is too large.

• B. It is an insulator.

• C. It is a conductor.

• D. It is made of metal.

Which observation is MOST LIKELY evidence that a chemical change is taking place?

• A. A solid changes shape when a student bends it.

• B. Bubbles form when a student heats a liquid on a burner.

• C. The temperature of a liquid changes when a student pours it into a jar.

• D. The temperature of a solid changes when a student puts it in a freezer.

Which substance does not have a fixed volume or a fixed shape?

• A. ice in a freezer

• B. water in a lake

• C. water vapor in air

• D. snow in a snowman

Some students are planning an experiment. They need to be able to vary the strength of a magnet. Which type of magnet should they use?

• A. bar magnet

• B. electromagnet

• C. horseshoe magnet

• D. refrigerator magnet

Which of these is a chemical property?

• A. whether a substance folds

• B. whether a substance dissolves

• C. whether a substance reacts with oxygen

• D. whether a substance changes from a liquid to a gas.

A student designs an electric circuit with a fan. What happens at the fan?

• A. Electric current is turned on and off.

• B. Electric current creates a positive charge.

• C. Electrical energy is supplied to the circuit.

• D. Electrical energy is changed into another form of energy.