According to the balanced equation above, how many moles of hi would be necessary to produce 2.5 mol of i2, starting with 4.0 mol of kmno4 and 3.0 mol of h2so4?

Answer is 5.0 mol.

Explanation;

The balanced reaction between KMnO₄ and HI is

2KMnO₄ + 10HI + 3H₂SO₄ → 2MnSO₄ + K₂SO₄ + 5I₂ + 8H₂O

The stoichiometric ratio between HI and I₂ is 2 : 1.

Hence, moles of HI needed = moles of 5I₂ produced x 2

= 2.5 mol x 2

= 5.0 mol