Properties of Water

What word describes when water is attracted to other substances?

• cohesion
• adhesion
• capillary action
• surface tension

What two elements make up water?

• Helium and oxygen
• Hydrogen and oxygen
• helium and carbon
• oxygen and carbon

Why does ice float?

• As water freezes, it expands and its density decreases.
• As water freezes, it takes up more hydrogen from the atmosphere, causing it to have a greater buoyancy.
• As water freezes, air becomes trapped between the hydrogen bonds of water molecules.
• As water freezes, it takes up more oxygen from the atmosphere, causing it to have a greater buoyancy.

Water is a universal solvent because it...

• It can be found anywhere
• It freezes when it gets cold
• floats when frozen
• Dissolves most substances

Which of the following is LEAST likely to dissolve in water?

• nonpolar fats and oils
• polar sugar molecules
• salt made of a positive sodium ion and a negative chloride ion
• all of the substances will dissolve easily in water

Large bodies of water, such as lakes and oceans, do not quickly fluctuate in temperature. What is the reason for this phenomenon?

• Water is an acid.
• Water is a versatile solvent.
• Water has a high heat capacity.
•  Water acts as a buffer.

 Small insects can walk across the surface of calm water. Their feet push the surface of the water down slightly, somewhat like a person walking across a trampoline, but they do not break the surface. What is the best explanation for why this happens?

• The insects are light enough so that they do not break the hydrogen bonds holding the water molecules together
• The insects actually use their wings to hover slightly above the water's surface and they only skim it with their feet
• The insects' feet are non-polar, so they are repelled by the polar water molecules and are pushed away from the water's surface
• The insects are small enough to see the individual water molecules, so they are able to step carefully from one molecule to the next

Which statement explains why water molecules stick together?

• both sides are negative
• one side has a positive charge and the other side has a negative charge
• one side has a negative charge and the other side has a neutral charge

• both sides are positive

The smallest basic unit of matter is the

• molecule.
• atom.
• compound.
• cell.

What characteristic is shown in the image?

• Polarity

• Hydrogen Bonds

• Cohesion

• Adhesion