Question

If you mix 2.8 mol of A with 2.8 mol of B, what amount (moles) of A2B can be produced?

Answer 1

Answer: 1.4 mol A2B is produced.

Explanation: 2A + B = A2B, so there are 2 moles of A to every one mole of B.

So if 2.8 mol of A is present 1/2 that amount is made in A2B (and there will be extra B left over because A is the limiting reactant and you can't make more product than the least amount of reactant allows.

So 1.4 mole of A2B will be produced.