Give the electron dot structures of the propanone and propanal.

Elements A, B, C and D belong to groups of periodic table as shown in the table above. 
(i) Is C a metal or non-metal? 
(ii) Which is more reactive, C or A? 
(iii) Which will be smaller, B or C? 
(iv) Name the family to which A belongs. 
(v) What is the valency of B. 
(vi) The formula of $\delta$ compound formed between D and C.
 

Balance the chemical equation:

$\mathrm{Fe}\left(\mathrm{s}\right)+{\mathrm{H}}_2\mathrm{O}\left(\mathrm{g}\right)\to {\mathrm{Fe}}_3{\mathrm{O}}_4\left(\mathrm{s}\right)+{\mathrm{H}}_2\left(\mathrm{g}\right)$

Identify the type of reaction in the equation given below:

${\mathrm{Na}}_2{\mathrm{SO}}_4\left(\mathrm{aq}\right)+{\mathrm{BaCl}}_2\left(\mathrm{aq}\right)\to {\mathrm{BaSO}}_4\left(\mathrm{s}\right)+\mathrm{NaCl}\left(\mathrm{aq}\right)$

What do you observe when you drop a few drops of acetic acid to a test tube containing : 

(i) phenolphthalein 

(ii) distilled water 

(iii) universal indicator

(iv) sodium hydrogen carbonate

While studying the double displacement reaction, the solutions of barium chloride and sodium sulphate are mixed together.

(i) What do you observe as soon as the two solutions are mixed? 

(ii) What will happen in the above observation made by you after ten minutes?