Chapter 9 Solutions — The Amazing World of Solutes, Solvents, and Solutions

Keep the Curiosity Alive

1. 1.
   State whether the statements given below are True [T] or False [F]. Correct the false statement(s).

   • (i) Oxygen gas is more soluble in hot water rather than in cold water.
   • (ii) A mixture of sand and water is a solution.
   • (iii) The amount of space occupied by any object is called its mass.
   • (iv) An unsaturated solution has more solute dissolved than a saturated solution.
   • (v) The presence of…
2. 2.
   Fill in the blanks.

   • (i) The volume of a solid can be measured by the method of displacement, where the solid is __________ in water and the ____________ in water level is measured.
   • (ii) The maximum amount of _______________ dissolved in _______________ at a particular temperature is called solubility at that temperature.
   • (iii) Generally, the density ____________ with increase in temperature…
3. 3.
   You pour oil into a glass containing some water. The oil floats on top. What does this tell you?

   • (i) Oil is denser than water
   • (ii) Water is denser than oil
   • (iii) Oil and water have the same density
   • (iv) Oil dissolves in water
4. 4.
   A stone sculpture weighs 225 g and has a volume of 90 cm³. Calculate its density and predict whether it will float or sink in water.
5. 5.
   Which one of the following is the most appropriate statement, and why are the other statements not appropriate?

   • (i) A saturated solution can still dissolve more solute at a given temperature.
   • (ii) An unsaturated solution has dissolved the maximum amount of solute possible at a given temperature.
   • (iii) No more solute can be dissolved into the saturated solution at that temperature.
   • (iv) A…
6. 6.
   You have a bottle with a volume of 2 litres. You pour 500 mL of water into it. How much more water can the bottle hold?
7. 7.
   An object has a mass of 400 g and a volume of 40 cm³. What is its density?
8. 8.
   Analyse Fig. 9.25a and 9.25b. Why does the unpeeled orange float, while the peeled one sinks? Explain.
9. 9.
   Object A has a mass of 200 g and a volume of 40 cm³. Object B has a mass of 240 g and a volume of 60 cm³. Which object is denser?
10. 10.
    Reema has a piece of modeling clay that weighs 120 g. She first moulds it into a compact cube that has a volume of 60 cm³. Later, she flattens it into a thin sheet. Predict what will happen to its density.
11. 11.
    A block of iron has a mass of 600 g and a density of 7.9 g/cm³. What is its volume?
12. 12.
    You are provided with an experimental setup as shown in Fig. 9.26a and 9.26b. On keeping the test tube (Fig 9.26b) in a beaker containing hot water (~70 °C), the water level in the glass tube rises. How does it affect the density?