Changes of State

Changes of State

and heating

Multiple Choice

What is the change of state that occurs when water at 10^o C is heated 50^o C ?

• ice changes to water

• water changes to ice

• steam changes to water

• water changes to water vapor

Multiple Choice

During the process of sublimation

• a solid turns directly into a gas

• a liquid turns to a gas

• a solid turns into a liquid

• a gas turns directly into a solid

Multiple Choice

The characteristic temperature at which a pure solid changes to a liquid is its __________ point.

• melting

• boiling

• Schaffer

• pressure

Multiple Choice

Condensation occurs when warmer water vapour comes into contact with a _______________ surface, loses heat and condenses into water droplets.

• warm

• warmer

• cool

• cooler

Multiple Choice

When Dylan got off from an air-conditioned bus, the lens of his spectacles became blurred. What caused this to happen?

• Warmer water vapour from the air-conditioned bus came into contact with a cooler outer surface of his spectacles' lens, lost heat and condensed into water droplets.

• Warmer water vapour from the surrounding air came into contact with a cooler outer surface of his spectacles' lens, gained heat and condensed into water droplets.

• Cooler water vapour from the air-conditioned bus came into contact with a warmer outer surface of his spectacles' lens, gained heat and condensed into water droplets.

• Warmer water vapour from the surrounding air came into contact with a cooler outer surface of his spectacles' lens, lost heat and condensed into water droplets.

Multiple Choice

On a hot, humid summer day drops of water form on a can of cold soda. What process caused this to happen?

• condensation

• freezing

• vaporization

• deposition

Multiple Choice

Solids have a __________ volume and ___________ shape.

• Definite, Definite
• Definite, Indefinite
• Indefinite, Definite
• Indefinite, Indefinite

Multiple Choice

On a "heat curve" what increases with time?

• Phase

• Heat

• Loss of Heat

Multiple Choice

What is the state of the substance at point A?

• Liquid

• Solid

• Gas

• Plasma

Multiple Choice

What is the state of the substance at point C?

• Liquid

• Solid

• Gas

• Plasma

Multiple Choice

What is the state of the substance at point E?

• Liquid

• Solid

• Gas

• Plasma

Multiple Choice

What phase change is happening at point B?

• Vaporization

• Sublimation

• Condensation

• Melting

Multiple Choice

What phase change is happening at point D?

• Vaporization

• Sublimation

• Freezing

• Melting

Multiple Choice

You pop into a restaurant and fancy some freshly cooked lobster. The waiter asks you to select one. Which would cook quickest?

• Lenny, he has the largest surface area

• Gottfried, it he has the lowest mass

• The all cook at the same time, as it is the temperature needed to be cooked.

• Laura as she has the largest surface to volume ration.

Poll

So to heat 1kg of water (specific heat capacity 4200 J/kg°C) up by just 2°C we would need how much heat?

• 2100 J

• 4200 J

• 8400J

Fill in the Blanks

Chef Michelle plans to cook Lenny for the Mayor’s lunch. How much energy (in Joules) is needed to heat the pan of water by 70°C?

Mass of water = 5.7 kg Specific heat capacity of Water = 4200/J°C

Fill in the Blanks

Lenny is dangling above the pot of boiling water. How much energy (in J, don't type the unit) will be needed to raise Lenny’s temperature by 40°C?

Lenny’s mass = 2.3kg

Specific heat capacity of Lobster = 3430kg/J°C

Fill in the Blanks

Gottfried unleashes his 600°C lobsteraser vision, melting the concrete floor beneath chef Michelle. How much energy did Gottfried unleash?

Mass of floor = 18kg

Specific heat capacity of Concrete = 850kg/J°C