A: Alkali metals can be extracted by chemical reduction

R: Alkali metals are weak reductants.

1. Both Assertion & Reason are true and the reason is the correct explanation of the assertion.

2. Both Assertion & Reason are true but the reason is not the correct explanation of the assertion.

3. Assertion is a true statement but Reason is false.

4. Both Assertion and Reason are false statements.

A substance that gives a brick red flame and breaks down on heating giving oxygen and a brown gas is-

1. Calcium carbonate.

2. Magnesium carbonate.

3. Magnesium nitrate.

4. Calcium nitrate.

All group-2 metals dissolve in liquid ammonia to produce a bright blue colour. The colour is due to-

1. A change in the structure of ammonia.

2. d-d transition.

3. The spectrum of the solvated electrons.

4. An electronic transition from a lower to a higher energy state.

The fire extinguisher contains NaHCO₃ and the compound (X). The compound (X) maybe -

1. CH₃COOH

2. NaOH

3. C₆H₅OH

4. None of the above. 

${\left({\mathrm{NH}}_4\right)}_2{\mathrm{Cr}}_2{\mathrm{O}}_7$ on heating (below 200 degrees celsius) liberates a gas. The same gas will be obtained below 600 degrees celsius by :

1. Heating ${\mathrm{NH}}_4{\mathrm{NO}}_2$

2. Heating ${\mathrm{NH}}_4{\mathrm{NO}}_3$

3. Heating ${\mathrm{Mg}}_3{\mathrm{N}}_2$

4. None of the above

The incorrect statement among the following is : 

1. The atomic radius of Na is greater than that of Mg.

2. Density of K is more than Na.

3. Melting point & boiling point of Ca are greater than those of Mg.

4. Mg does not react with cold water.

A Brine solution on electrolysis will not give : 

1.  NaOH

2.  ${\mathrm{Cl}}_2$

3.  ${\mathrm{H}}_2$

4.  ${\mathrm{O}}_2$

Out of Be, Mg, Ca, Sr and Ba,

Total number of metal whose nitrates are decomposed according to the following reaction are:

2M(NO₃)₂ $\stackrel{∆}{\to }$ Residue + 4NO₂ + O₂

1. 5

2. 4

3. 3

4. 2

 An amphoteric hydroxide among the following is : 

1.  $\mathrm{Be}{\left(\mathrm{OH}\right)}_2$

2.  $\mathrm{Sr}{\left(\mathrm{OH}\right)}_2$

3.  $\mathrm{Ca}{\left(\mathrm{OH}\right)}_2$

4.  $\mathrm{Mg}{\left(\mathrm{OH}\right)}_2$