States of Matter and Thermal Energy

Matter, Thermal Energy, and Water Cycle Review

Fall 2020

States of Matter

• Solid: Most dense, tightly packed molecules

• Liquid: Less dense, molecules more spread out and move faster than in a solid

• Gas: Least dense, molecules are very spread out and move very fast

Multiple Choice

Ice was left on the counter and it melted into a puddle of water. What happened to the molecules as the ice cube melted?

• The molecules froze

• The molecules slowed down and came together

• The molecules moved faster and spread apart

• The molecules evaporated

Multiple Choice

A cup of water was left out in the sun. At the end of the day, the water level had gone down from 30ml to 18ml. What happened to the water?

• It condensed

• It evaporated

• It boiled

• It melted

Conservation of Mass

• Physical Change - no new substance forms (can usually be reversed)

• Chemical Change - a new substance forms (cannot be reversed)

• Law of Conservation of Mass: Matter cannot be created or destroyed. Therefore, during a physical or chemical change, mass does not change. It remains constant. For example, if ice weighs 20g, when it melts into water, that water will also weigh 20g.

Multiple Choice

Sam is baking a cake. The flour has a mass of 50 grams, the sugar has a mass of 30 grams, the eggs have a mass of 20 grams, and the water has a mass of 10 grams. How much does the cake weigh after it has been baked?

• 100 grams

• 110 grams

• 50 grams

• Impossible to determine

Multiple Choice

A pile of logs weighs 550 grams. The logs were burned into a pile of ash. The smoke from the burning logs weighs 50 grams. How much does the pile of ash weigh?

• 50 g

• 500 g

• 550 g

• 600 g

Multiple Choice

Dr. Kemp was making lemonade. She added 10g of sugar and 5g of lemon to 20g of water. The sugar dissolved in the water. What is the mass of her glass of lemonade?

• 20g

• 25g

• 35g

• 10g

Thermal Energy Transfer

• Conduction: transfer of heat through direct contact

• Convection: transfer of heat through a liquid or gas

• Radiation: transfer of heat through electromagnetic rays

Multiple Choice

Which of the following is an example of conduction?

• a heater warming a room

• burning your feet on hot pavement

• water boiling

• getting a tan from the sun

Multiple Choice

Which of the following is an example of radiation?

• ironing a shirt

• a metal spoon in a cup of coffee

• feeling warmth from a fire

• a hot air balloon

Multiple Choice

Which of the following is an example of convection?

• hot air rising to the attic of your house

• the sun's rays warming your skin

• touching a hot plate

• sitting around a campfire

Water Cycle

• Evaporation

• Transpiration

• Condensation

• Preciptation

• Run-off

Multiple Choice

How are clouds formed?

• Evaporation

• Condensation

• Transpiration

• Precipitation

Multiple Choice

Water evaporating from plants and trees is called

• Evaporation

• Condensation

• Transpiration

• Condensation