Physical or Chemical Changes
Bubbles appear, new smell, temperature changes, color changes.
I touch a metal rod and burn my hand, that is heat transfer through what?
Conduction
What kind of pan would I need to cook my steak evenly?
Metal
Expand means to get what?
Bigger
Tom mixes 10g of water with 5g of salt, how much does his mixture weigh now?
15g
I break a glow stick and it starts to glow. What is this an example of?
A chemical change
Why is a cloudy day cooler?
The clouds block the radiation from the sun.
What material would be best to store ice cream in so it doesn't melt?
Plastic
Contracts means to get what?
Smaller
Bill has 20g of ice cream in a cup. The ice cream melts, how much does the cup weigh now?
20g
I heat up plastic and melt it to a liquid, this is an example of what?
A physical change
Which heat transfer deals with gasses and liquids?
Convection
What color shirt should I wear on a hot summer day to reflect heat?
White
Tom can't open his metal pickle jar lid. Why would putting it under hot water make it easier to open?
The heat will expand the metal lid, making it open.
Bill has 50g of water. 10g evaporate, how much water does Bill have now?
40g
The wax melting is a physical change while the wick burning is a chemical change.
Which heat transfer is the cause for heating of the air in our atmosphere?
Convection
Why do builders put insulation in attics?
Because hot air rises and the insulation traps it.
Why do they build bridges with small gaps in them?
Because heat will cause the cement to expand and without the gaps, the bridge with crack.
A rock weighs 10g and is broken into 2 pieces. What could be the weight of the 2 rocks?
5g and 5g
6g and 4g
7g and 3g
Why is water vapor changing to liquid water an example of a physical change?
The molecules are still H2O. Changing states of matter is still physical changes.
Conduction
What kind of material is space ships made out of?
Ceramic
I throw boiling water on a frozen window and the window cracks. Why?
The sudden heat change expanded the glass so fast it broke.
As gold mets, the weight will...
stay the same