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
Which has lowest thermal stability?
1. Li2CO3
2. Na2CO3
3. K2CO3
4. Rb2CO3
An alkali metal that reacts with nitrogen to form nitride is -
1. Li
2. Na
3. Cs
4. None of the above.
Caustic soda is:
1. Efflorescent
2. Deliquescent
3. Hygroscopic
4. Oxidant
The most basic oxide among the following is:
1. Na2O
2. BaO
3. As2O3
4. Al2O3
Pearl ash and caustic potash are chemically:
1. K2CO3 and KOH
2. KOH and K2CO3
3. Na2CO3 and KOH
4. Na2CO3 and NaOH
The most dangerous method of precipitating hydrogen would be by the action of HCl on:
1. Zn
2. Fe
3. K
4. Al
Which is industrially prepared by the electrolysis of aqueous NaCl?
1. Na2CO3
2. NaHCO3
3. NaOH
4. NaOCl
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
Sodium cannot be extracted by the electrolysis of brine solution because:
1. sodium leberated reacts with water to produce NaOH+H2
2. sodium being more electropositive than hydrogen, H2 is liberated at cathod and not sodium
3. electrolysis cannot take place with brine solution
4. none of the above