Heat transfer & molecular motion

Hot coffee is stirred with a spoon; the spoon gets hot due to

• conduction
• convection
• radiation

"Lava lamps" contain colored liquids. These liquids form globs that rise to the top due to

• conduction
• convection
• radiation

Conduction can only occur between two objects when –

• one object is less dense than the other.
• both objects are in physical contact with each other.
• one of the objects is made of a metal.
• both objects are exactly the same temperature.

In this demonstration, what causes the balloon to expand?

• The heat from the room causes the balloon to expand.
• The heat from the hot plate heats the glass and the air inside it expands.
• The balloon spontaneously blows up to try to escape the bottle. 
• I don't know.

Which type of motion in the figure best represents the movement of gas particles?

• Motion 1

• Motion 2

• Motion 3

• Motion 4

What happens to matter as its temperature increases?

• The average kinetic energy of its particles decreases

• The average thermal energy of its particles decreases

• The particles gain kinetic energy

• The particles lose potential energy

The more energy that particles have, the ___ they move.

• slower

• faster

Which process could cause a material to change state from gas to liquid?

• Adding heat

• Adding energy

• Removing particles

• Removing energy

What state of matter does the picture best describe?

• Solid
• Liquid
• Gas

Temperature

• measure of heat or how fast molecules are moving
• the coldest possible temperature.
• water vapor cools and becomes a liquid
• A molecule composed of one kind of atom; cannot be broken into simpler units- ex hydrogen, helium, gold