Formation of Precipitate

Q. Sodium reacts with cold water to form:

1. Sodium hydride and oxygen
2. Sodium hydroxide and hydrogen
3. Sodium hydroxide and oxygen
4. Sodium hydride only

Q.

What is the colour of precipitate formed when lead nitrate reacts with potassium iodide?

1. Yellow

2. Black

3. Green

4. Blue

Q.

You are given the solution of lead nitrate. In order to obtain a yellow precipitate you should mix with it a solution of :

(a) potassium chloride (b) potassium nitride

(c) potassium sulphide (d) potassium iodide

Q.

$AgN{O}_{3\left(aq\right)}+NaC{l}_{\left(aq\right)}\to AgC{l}_{\left(s\right)}+NaN{O}_{3\left(aq\right)}$.
Above reaction involves formation of precipitate.

1. False

2. True

Q.

Barium chloride on reacting with sodium sulphate forms barium sulphate and sodium chloride. Which of the following is the precipitate?

1. Barium chloride

2. Barium sulphate

3. Sodium sulphate

4. Sodium chloride

Q.

Precipitates are _____ substances.

1. soluble

2. insoluble

3. little soluble

4. readily soluble

Q. When carbon dioxide gas is passed through lime water,

1. calcium hydroxide is formed.
2. white precipitate of CaO is formed.
3. white precipitate of $CaC{O}_3$ is formed.
4. colour of lime water disappears.

Q. When ferrous sulphate $\left({\text{FeSO}}_4\right)$ solution combines with sodium hydroxide $\text{(NaOH)}$, the chemical change is identified by the .

1. formation of gas
2. formation of ppt
3. absoprtion of heat

Q. When ferrous sulphate $\left({\text{FeSO}}_4\right)$ solution combines with sodium hydroxide $\text{(NaOH)}$, the chemical change is identified by the .

1. formation of gas
2. formation of ppt
3. absoprtion of heat

Q. Sam blows air into limewater using a straw. He notices that the limewater turns milky. Identify the gas responsible for the change and the type of change involved.

1. Gas - oxygen
   Change - chemical
2. Gas - carbon dioxide
   Change - chemical
3. Gas - oxygen
   Change - physical
4. Gas - carbon dioxide
   Change - physical