1. One reason water is an effective solvent is that it —
A contains an oxygen atom
B is a polar molecule
C has a freezing point of 0°C
D can evaporate easily

2. What characteristic of water remains the same no matter what is dissolved in it?
A The ratio of hydrogen to oxygen
B The ability to refract light
C The hydroxide ion concentration
D The freezing temperature .

3. Which factor makes water an effective solvent?
A The presence of molecular oxygen
B Its lack of covalent bonds
C The polar nature of its molecules
D Its abundance on Earth’s surface


4. As a scuba diver goes deeper underwater, the diver must be aware that the increased pressure affects the human body by increasing the —
A body’s temperature
B amount of dissolved gases in the body C amount of suspended solids in the body
D concentration of minerals in the body

5. A recipe calls for 210 grams of sugar to be dissolved in 0.25 liter of water. After the mixture is stirred, some sugar crystals remain in the water. What can be added to the mixture to help dissolve the remaining sugar crystals?
A Thermal energy B 2.0 g of baking soda
C Ice cubes D 2.0 g of sodium chloride​