C is an organic compound. Carry out the following exercises on C. Record your observations and identity any gas(es) evolved. State the conclusions you draw from the results of each test.

(a) Put about 10 drops of C on a watch glass and ignite it using a burning splint.

(b)(i) Put about 1 cm\(^3\) of C in a test tube and add about 1 cm\(^3\) of distilled water. Shake the test tube.

(ii) Put about 1 cm\(^3\) of C in a test tube and add about 2 cm\(^3\) of acidified K\(_2\)Cr\(_2\)O\(_7\) solution. Warm the mixture gently and leave to stand for 5 minutes.

(c) Put few crystals of specimen D in a test tube and add about 2cm\(^3\) of C followed by about 2 cm\(^3\) of 10 % NaOH\(_{(aq)}\) Shake the test tube vigorously.

(d) State the class of compounds to which C belongs.
 

(a) A zinc salt, E when heated strongly, produced a brown gas with pungent smell, a colourless gas that rekindled a glowing splint, and a residue that was allowed to cool.

(i) identify the salt E.

(ii) Write an equation for the decomposition of E.

(iii) State what would be observed when the residue was allowed to cool.

(b) Describe how 250cm\(^3\) of 0.2 mol dm\(^3\) H\(_2\)SO\(_4\) could be prepared from 150 cm\(^3\) of a 1.0 mol dm\(^{3}\) stock solution of the acid.

(c) State the effect of aqueous solution of Al\(_2(SO_4)_3\) on litmus paper.