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what are the three states of matter
solid, liquid, gas
What is melting point?
When a substance changes from solid to liquid
What is freezing point?
When a substance changes from liquid to solid
Are melting point and freezing point the same?
Yes
Are boiling point and condensing point the same?
Yes
What is sublimation?
When a liquid turns directly into a gas without first becoming a liquid
Which state(s) are considered fluids?
Liquids and gases
Is evaporation or condensation endothermic?
Evaporation. Heat is added to turn a liquid to a gas, heat is removed to turn a gas into a liquid = condensation (exothermic)
How does surface area affect rate of evaporation?
Greater surface area faster the rate of evaporation
What is meant by a volatile liquid?
It has a low boiling point, it easily condenses
How does an increase in pressure affect boiling point?
Directly related. An increase in pressure= an increase in boiling point
What affect does a decrease in pressure have on the volatility of a liquid?
Increase. If you decrease the pressure (on a mountain top) that decreases the boiling point (boils easier) a volatile liquid is one the has a low boiling point.
At what temperature does water become ice?
0 degrees C, it is the same temperature ice becomes water. (mp = fp)
At what temperature does water vapor become water?
100 degrees C. Same temp that water becomes water vapor bp=cp
What affect does an impurity have on boiling point and melting point
Lowers melting point, raises boiling point
Is H2 a compound or an element
Element
