Observations That Help Determine Chemical Change

Q.

White silver chloride in sunlight turns to

1. red

2. grey

3. yellow

4. remain white

Q.

Gas is evolved in which of the chemical reaction?

1. Silver Nitrate is added to a Sodium Chloride solution.

2. Zinc reacting with dilute sulphuric acid

3. Iron dropped into copper sulphate solution.

4. Ammonia Gas reacting with Hydrochloric Acid.

Q. Which metal can replace copper from copper sulphate solution ?

1. Hg
2. Pt
3. Au
4. Fe

Q. Paheli prepared a blue coloured solution of copper sulphate in beaker A and placed an iron nail in it. Boojho prepared a yellowish green solution of ferrous sulphate in beaker B and placed a copper wire in it. What changes will they observe in the two beakers after an hour?

Q. $Fe+CuS{O}_4\to$ _____ + _____

1. $FeS{O}_2,C{u}_2$
2. $FeS{O}_4,Cu$
3. $F{e}_{2}S{O}_4,Cu$
4. None of above

Q.

When washing soda is treated with hydrochloric acid, it gives off colourless gas with lot of effervescence, then that gas is

1. $C{O}_2$

2. $CO$

3. $C{l}_2$

4. $O_2$

Q. Match the following concentration methods with the principle behind them.

1. Magnetic property
2. Specific gravity
3. Differential wetting property

Q. _________ is formed as a result of chemical reaction.

1. Ink
2. Air
3. Water
4. Lemon juice

Q.

Why does the color of sulphate solution change when an iron nail is dipped in it?

Q. Gravity separation is also called ___ .

1. levigation
2. levitation
3. magnetic seperation
4. distillation