Which ion forms a hydroxide highly soluble in water?

1. Ni²⁺

2. K⁺

3. Zn²⁺

4. Al³⁺

What would you observe if excess of dilute NaOH solution is added and shaken with an aqueous solution of aluminium chloride?

1. A permanent white precipitate is formed immediately

2. No change at first but a white precipitate is formed on standing

3. A white precipitate is formed which later dissolves

4. A green precipitate which turns red on standing in air

A colourless salt gives violet colour to Bunsen flame and also turns moistured litmus paper blue. It Is:

1. Na₂CO₃

2. KNO₃

3. K₂CO₃

4. Cu(OH)₂

Strongest reducing agent among the following is:

1. K

2. Na

3. Al

4. Mg

When crystal of caustic soda is exposed to air, a liquid layer is deposited because:

1. crystal melts

2. crystal loses water

3. crystal absorbs moisture and CO₂

4. crystal sublimes

Which one of the following is formed on dissolving I₂ in aqueous solution of KI ?

1. KIO₄

2. KIO

3. KI₃

4. KIO₃

Which of the following statements is correct for CsBr₃?

1. it is a covalent compound

2. It contains Cs²⁺ and Br^- ions

3. It contains Cs⁺, Br^- and Br₂ lattice molecules

4. It contains Cs⁺ and ${\mathrm{Br}}_3^{-}$ ions

Hypo is chemically:

1. Na₂S₂O₃.2H₂O

2. Na₂S₂O₃.3H₂O

3. Na₂S₂O₃.4H₂O

4. Na₂S₂O₃.5H₂O

If NaOH is added to an aqueous solution of Zn²⁺ ions, a white precipitate appears and on adding axcess NaOH, the precepitate dissolves. In this solution zinc exists in the:

1. cationic part

2. anionic part

3. both in cationic and anionic parts

4. there is no zinc left in the solution

Brine is chemically:

1. conc. solution of Na₂CO₃

2. conc. solution of Na₂SO₄

3. conc. solution of NaCl

4. conc. solution of alum