Heat/Matter/Conservation of Matter
Helpful Videos:
Force and Motion:
Vocabulary:
- Conduction: transfer of heat through solids touching
- Example: touching a hot burner, a spoon heating in a bowl of soup
2. Radiation: transfer of heat through electromagnetic waves (empty space)
- Example: roasting marshmallows over a campfire, heat from a light bulb, using a microwave, radiator heat, heat from a candle burning
3. Convection: heat transfer through liquid and gases, and air
- Examples: heater heating a building or home, a heater in a swimming pool, sea breeze and land breeze, hot air balloon, hot air popcorn popper, cooking macaroni on the stove top.
4. Conductors of heat: allow heat to travel through easily
- Examples: metal, copper, iron, silver, nickel
5. Insulators: do NOT allow heat to travel through easily
- Examples: plastic, wood, oven mit
6. Mixture: when the parts can be separated
- Examples: trail mix, cereals like Lucky Charms
7. Conservation of Matter: Matter cannot be destroyed or created
8. Chemical Change: A change that cannot be reversed
- Characteristics: produces a fizz, a light, a gas, changes color or makes a new substance like rust, ash, or tarnish
9. Physical Change: a change that can be reversed
- Characteristics: bending, cutting, reshaping, folding, melting, or changing the state of matter.
- ANYTHING WITH WATER IS ALWAYS PHYSICAL CHANGE
Study notes:
- Conduction:
- transfer of heat through touching
- Conduction=”con-touching”
- Wearing oven mitts allows heat to not be conducted when removing from oven
- Convection:
- transfer of heat through liquids and gases
- Air, liquids, gases
- Includes sea breezes and land breezes
- The uneven heating of the atmosphere is caused by convection
- Green houses get warmed from radiation, but the inside stays warm because warm air begins to rise and cool air sinks
- Hot air inside of an hot air balloon rises because of convection. This is movement of heat through gases and liquids.
- Hot air expands inside of a hot air balloon because the hot air is less dense than the cooler air outside of the balloon.
- When the ground is heated by the sun, the air above the ground becomes warm and rises-the air rising is convection.
- Sea breezes and land breezes are created because of convection.
- Convection is the source of heat transfer that moves thermal energy around the Earth.
- Climate is impacted by convection.
- Heating the atmosphere is convection because the atmosphere is “air” and warm air rises and cold air sinks
- Heat sparks rise because of convection
- Radiation:
- Transfer of heat by waves through empty space
- The sun warming your skin
- Greenhouses get warm by radiation
- Heat transfer through the air by radiation
- Grass converts the radiation heat from the sun into photosynthesis
- When the sun shines through a window and a table is warmed, this is radiation because the heat travelled through electromagnetic waves
- Radiation is the original source of energy for Earth.
- When a hot dog is placed over a fire, the hot object is the fire and the cooler object is the hot dog. The fire transfers heat to the hot dog through radiation
- Heat from a campfire radiates heat to people standing near the fire. The fire is the warmer object and the people are the cooler objects.
- Clouds block sun's radiation heat, which keeps the sun's heats from warming the air. This causes temperatures to be lower.
Heat:
- Heat travels from HOT to COLD
- When you add ice to a cup of water, the warmer object is the water and the colder object is the ice.
- The hotter object will always lose its heat energy to the cooler object
- This is why ice melts in liquids
- When a hot spoon is placed inside of a gallon of ice cream, the hotter object is the spoon and the cooler object is the ice cream
- This is why the spoon loses its heat energy to the ice cream causing it to melt where the spoon touches the ice cream
- This type of heat transfer would be conduction because it the spoon is touching the ice cream
Conductors/insulators:
- Allows heat to pass through easily
- Plastic is a poor conductor of heat so it is used to cover handles on metal pots
- Plastic conducts the least amount of heat