we have the following equation- 2HCl+CuSO4 yields H2SO4+CuCl2. the question is if 7 moles of HCl react, how many moles of H2SO4 will be produced?

I don't think the reaction will occur, at least not signifi8cantly. However, assuming it does, this is what you do.

Use the coefficients in the balanced equation.
7 mols HCl x (1 mol H2SO4/2 mols HCl) = 7 x (1/2) = ?

To find out how many moles of H2SO4 will be produced when 7 moles of HCl react, we need to use the stoichiometry of the balanced equation.

The balanced equation is:

2HCl + CuSO4 -> H2SO4 + CuCl2

From the balanced equation, we can see that 2 moles of HCl reacts with 1 mole of H2SO4.

So, to find the number of moles of H2SO4 produced, we first need to convert the given 7 moles of HCl into moles of H2SO4.

Using the ratio from the balanced equation, we can set up the following equation:

2 mol HCl / 1 mol H2SO4 = 7 mol HCl / x mol H2SO4

Cross-multiplying, we get:

2x = 7

Now, we can solve for x by dividing both sides of the equation by 2:

x = 7 / 2

Therefore, when 7 moles of HCl react, 3.5 moles of H2SO4 will be produced.