Highly soluble hydroxide in water is formed by -
1. Ni2+
2. K+
3. Zn2+
4. Al3+
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
Sodium reacts with water less vigorously than potassium because:
1. it has higher atomic weight
2. it is less electropositive
3. it is more electronegative
4. it is metal
Excess of dilute sodium hydroxide solution is gradually added with shaking to an aqueous solution of zinc sulphate. What would you observe?
1. A light blue precipitate is first formed which finally dissolves to give a deep blue solution
2. A white precipitate appears which dissolves to give a colourless solution.
3. A white precipitation is formed which does not dissolve
4. No change takes place and the solution remains clear
The most dangerous method of precipitating hydrogen would be by the action of HCl on:
1. Zn
2. Fe
3. K
4. Al
The products of the electrolysis of aqueous solution of common salt are:
1. Na + Cl2
2. H2 + O2
3. NaOH + H2 + Cl2
4. NaOH + Cl2 + O2
KO2 is used in oxygen cylinder in space air craft and submarines because it:
1. absorbs CO2 and increase O2 content
2. eliminate moisture
3. absorbs CO2
4. produces O2
Which one is the highest melting point halide?
1. NaCl
2. NaBr
3. NaF
4. NaI
Manufacture of NaOH is done by:
1. Castner - Kellner process
2. Solvay process
3. Brine process
4. Mond's process
Lithium is the only alkali metal which is not placed in kerosene but is wrapped in paraffin wax, because:
1. it reacts with kerosene
2. it floats to the surface of kerosene because of low density
3. it does not react with air and H2O
4. none of the above