3.7 quiz properties of water , lab safety, graphing

You can float a paper clip on top of water if you very carefully place it flat on the water surface because of the molecular skin created by the interaction of air molecules with the top layer of water molecules on the surface.

• true
• false

A lightning storm is more dangerous to someone swimming in pool water than it is to someone swimming in salty ocean water.

• true
• false

What term describes the temperature at which a substance can change state from a solid to a liquid?

• Melting point
• Boiling point
• Freezing point
• Specific heat

What age group are spending the most time with children?

• 10-20 year olds
• 30-40 year olds
• 50-60 year olds
• 60-70 year olds

In the image below, label b -What is an attraction between substances of the different kinds called ?

• surface tension
• capillary action
• adhesion
• cohesion

A water molecule is 'polar' because it looks like a seesaw: The oxygen atom is in the middle and hydrogen atoms are at opposite ends of the oxygen atom.

• true
• false

Water does not dissolve oil because

• water is ionic and oil is covalent
• oil is polar molecule and water is nonpolar molecule
• water is a polar molecule and oil is a nonpolar molecule
• water is covalent and so is oil.

What is the dependent variable in the graph below?

• price per bushel
• quantity demanded per week
• bushel
• 20 weeks

solid water floats on liquid water due to ice having a lower ___________ than liquid water.

• surface tension
• hydrogen bonds
• polarity
• density

Which of the following is NOT a property of water?

• It is a universal solvent
• it expands when it freezes
• It can erode rock
• It can change temperature quickly