TestubeA: KMnO4 + H2S04 + NaHSO3---->MnSO4+ K2SO4+Na2SO4 (colourless solution)

a) if test tube a wasn't acidic enough, what colour might you expect in the products.

Acidic solutions of KMnO4 are reduced to Mn(II). Neutral or basic solution of KMnO4 are reduced to MnO2. Mn(II) solution are faint pink, MnO2 is a brown solid. In solution this often is mixed with MnO(OH)2, also dark brown.

To determine the color of the products when Testtube A is not acidic enough, we need to understand the reaction taking place.

The reaction you provided is a redox reaction involving permanganate ions (MnO4-) and sulfite ions (SO3^2-). In acidic conditions, permanganate ions are reduced to manganese ions (Mn^2+), while sulfite ions are oxidized to sulfate ions (SO4^2-).

In this case, if Testtube A is not acidic enough, it means the concentration of hydronium ions (H3O+) is low. The reaction requires a sufficient amount of hydronium ions to provide the acidic environment necessary for the reduction of permanganate ions.

If the concentration of hydronium ions is not adequate, the reduction process might not occur fully or at all. As a result, the permanganate ions would remain in the solution without being converted into manganese ions.

In the absence of the reduction reaction, the solution would contain unreacted KMnO4, leading to a pink or purple color. KMnO4 is a purple-colored compound, and its presence without being reduced would result in a colored solution.

Therefore, if Testtube A was not acidic enough, we would expect a pink or purple color in the products instead of a colorless solution.