Question 2 :
The major role of fluorspar {tex}\mathrm {(CaF)}{/tex} which is added in small quantity in the electrolytic reduction of alumina dissolved in fused cryolite {tex} \left( \mathrm { Na } _ { 3 } \mathrm { AlF } _ { 6 } \right) {/tex} is :- <br>(a) as a catalyst <br>(b) to make the fused mixture very conducting <br>(c) to lower the temperature of melting <br>(d) to decrease the rate of oxidation of carbon at the anode

Question 3 :
One of the elements present in carnallite shows flame colouration. The colour of the flame is

Question 8 :
Which element has high concentration in plants, as compared to sodium?

Question 9 :
A metal carbonate,$M_xCO_3$, is heated in a closed container and the product is passed through lime water and lime water turns milky.The metal $M$ can be:

Question 10 :
The table shows some reactions of a white compound, G.<br/><br/><table class="wysiwyg-table"><tbody><tr><td>Test</td><td>Observation</td></tr><tr><td>Silver nitrate is added to a solution of G followed by aqueous ammonia</td><td>A precipitate is formed which does not dissolve when the ammonia is added</td></tr><tr><td>Solid G is warmed with concentrated sulfuric acid</td><td>A mixture of gases is formed including hydrogen sulphide</td></tr></tbody></table><br/><div>What could be the identity of G?<br/></div>

Question 11 :
A compound of sodium does not give $CO_2$ when heated but it gives $CO_2$ when treated with dilute acids. A crystalline compound is found to have 37.1% Na and 14.52% $H_2O$. Hence, the compound is :

Question 12 :
Which of the&#160; following statement about LiCl and NaCl&#160; is correct?

Question 15 :
Caustic soda is insoluble in Water,ethanol and methanol.<br/><p>State True or False:<br/></p>