1. One kg of air is compressed from 1 m3 to 0.5 m3. Which of the following statements is true?   The density is doubled.   The density is halved.   The mass is doubled.   The mass is halved.   Hint Half-n-half Clue   2. Water has the maximum density at   40oC   4oC   -4oC   0oC   Half-n-half Clue   3. The density of air is about 1 g/cm3 at room temperature and atmospheric pressure.   True   False   4. The density of carbon dioxide is 1.8 kg/m3. So, the volume occupied by 9.0 kg of carbon dioxide is   0.2 m3   16.2 m3   None of these   5 m3   Half-n-half Clue   5. The density of water is about 100 kg/m3 at room temperature.   True   False   6. An object floats in liquid L1, but it sinks to the bottom in liquid L2. Which statement of the following is true?   No definite conclusion can be made about the liquid densities.   Liquid L1 has a lower density than liquid L2.   Liquids L1 and L2 have the same density.   Liquid L1 has a higher density than liquid L2.   Half-n-half Clue   7. Which of these has the highest density?   Water   Mercury   Tungsten   Lead   Half-n-half Clue