Investigating Heat Study Guide

Front

What is the Joule-Thompson effect?

Back

The Joule-Thompson effect is a phenomenon where a gas cools down when it expands without doing external work.

Front

What happens to air when a volleyball is released and contains too much air?

Back

The air feels cold due to the Joule-Thompson effect as it expands.

Front

How do you calculate the rate of heat transfer?

Back

Rate of heat transfer = (Initial temperature - Final temperature) / Time observed.

Front

What is the rate of heat transfer for an object that cools from 50°C to 40°C in 5 minutes?

Back

2 °C/min.

Front

Why does the liquid in a thermometer rise when heated?

Back

The particles in the liquid move faster and expand, causing the liquid to rise.

Front

What is a chemical change?

Back

A chemical change is a process where substances combine or break apart to form new substances, such as burning wood.

Front

What is an example of a physical change?

Back

Mixing sand and water is a physical change because no new substance is formed.

Front

What is evaporation?

Back

Evaporation is the process where liquid turns into vapor, often used by the body to cool down.

Front

What is the main purpose of evaporation in the body?

Back

To cool the body.

Front

What happens to particles in a substance when it is heated?

Back

The particles move faster and usually expand.