A is a solution containing 0.050mol/dm-3 of a tetraoxosulphate (iv). B is a solution of anhydrous sodium trioxocarbonate (iv). Put A into the burette and titrate with 20 or 25cm-3 portions B using methyl orange as an indicator. Record the volume of ur pipette. Given that the average titre volume is 22.50cm-3. [a] write the equation for the reation. [b] find the value of NA and NB. [c] calculate the concentration of B in mol/dm-3.