All your burette readings (initial and final) as well as the size size of your pipette, must be recorded but no account of experimental procedure is required. All calculations must be done in your answer book. 

Xg of pure potassium trioxocarbonate (IV) was treated with 1dm\(^3\) of 0. 25M tetraoxosulphate (VI) acid to obtain solution A which contains excess acid. B is a solution containing 2.8g of potassium hydroxIde per 250cm\(^3\) solution.

(a) Put A into the burette and titrate with 20cm\(^3\) or 25cm\(^3\) portions of B. using methyl orange as indicator. Record the volume of your pipette. Tabulate your burette readings and calculate the average volume of acid used.

(b) From your results and the information given. Calculate the;

(i) concentration of the excess acid in A in mol dm\(^3\)

(iii) value of X. The equation for the reaction between the excess acid the potassium hydroxide is H\(_2\)SO\(_4\) + 2KOH \(\to\) K\(_2\)SO\(_4\) [H = 1. C = 12, O = 16. S = 32, K = 39]