Q. Which of the following will show "Tyndall effect"?

1. Salt solution
2. Copper sulphate solution
3. Milk
4. Starch solution

Q. Which of the following are chemical changes?
$\left(a\right)$ Growth of a plant
$\left(b\right)$ Rusting of Iron
$\left(c\right)$ Mixing of iron fillings and sand
$\left(d\right)$ Cooking of food
$\left(e\right)$ Digestion of food
$\left(f\right)$ Freezing of water
$\left(g\right)$ Burning of a candle.

Q. Classify the following into elements, compounds and mixtures.
$\left(a\right)$ Sodium
$\left(b\right)$ Soil
$\left(c\right)$ Sugar solution
$\left(d\right)$ Silver
$\left(e\right)$ Calcium carbonate
$\left(f\right)$ Tin
$\left(g\right)$ Silicon
$\left(h\right)$ Coal
$\left(i\right)$ Air
$\left(j\right)$ Soap
$\left(k\right)$ Methane
$\left(l\right)$ Carbon dioxide
$\left(m\right)$ Blood

Q. Write the steps you would use for making tea. Use the words solution, solvent, solute, dissolve, soluble, insoluble, filtrate and residue.

Q. Classify each of the following as a homogeneous or heterogeneous mixture:
Soda water, wood, air, soil, vinegar, filtered tea.

Q. Which of the following materials fall in the category of a pure substance?
$\left(a\right)$ Ice
$\left(b\right)$ Milk
$\left(c\right)$ Iron
$\left(d\right)$ Hydrochloric acid
$\left(e\right)$ Calcium oxide
$\left(f\right)$ Mercury
$\left(g\right)$ Brick
$\left(h\right)$ Wood
$\left(i\right)$ Air

Q. Explain the following giving examples.
$\left(a\right)$ Saturated solution
$\left(b\right)$ Pure substance
$\left(c\right)$ Colloid
$\left(d\right)$ Suspension

Q. How would you confirm that a colourless liquid given to you is pure water?

Q. Identify the solutions among the following mixtures.
$\left(a\right)$ Soil
$\left(b\right)$ Seawater
$\left(c\right)$ Air
$\left(d\right)$ Coal
$\left(e\right)$ Soda water

Q. Which separation techniques will you apply for the separation of the following?
$\left(a\right)$ Sodium chloride from its solution in water.
$\left(b\right)$ Ammonium chloride from a mixture containing sodium chloride and ammonium chloride.
$\left(c\right)$ Small pieces of metal in the engine oil of a car.
$\left(d\right)$ Different pigments from an extract of flower petals.
$\left(e\right)$ Butter from curd.
$\left(f\right)$ Oil from water.
$\left(g\right)$ Tea leaves from tea.
$\left(h\right)$ Iron pins from sand.
$\left(i\right)$ Wheat grains from husk.
$\left(j\right)$ Fine mud particles suspended in water.

Q. Pragya tested the solubility of three different substances at different temperatures and collected the data as given below(results are given in the following table, as grams of substance dissolved in $100$grams of water to form a saturated solution).