If 3.0 moles of a and 4.0 moles of b react according to the hypothetical reaction below, how many moles of the excess reactant will be left over at the end of the reaction? a + 2b → ab2

1.0 mol of A should be left over.

Explanation:

We have the balanced equation:

That means that I need 1.0 mol of A for each 2.0 moles of B to obtain 1.0 mol of

Now, we have 3.0 moles of A and 4.0 moles of B reacting, so:

3.0 moles of A . = 3.0 moles of

4.0 moles of B . = 2.0 moles of

That means that with 3.0 moles of A and 4.0 moles of B, we can form 2.0 moles of and 1.0 mole of A should be left over.

the answer is c i took the test