How do you work out the concentration of a solution

A hydrogen peroxide solution is made up of:
1g potassium iodide
50mL, 1M sulphuric acid
25mL hydrogen peroxide solution
How do I work out the concentration of the hydrogen peroxide solution using this?
Thank you :)

You need to know the initial concentration of the hydrogen peroxide solution. Without that, you cannot calculate the final concentration. Even with that, you have to make a couple of assumptions concerning volume changes on mixing and so on. Given those assumptions, once you know the initial concentration, you could calculate the final concentration. Let's assume the H2O2 was initially 3%, then, the equation you use is:

M1V1 = M2V2
3%(25 mL) = x%(75 mL)
x% = 1%



I just read your additional details...No, you cannot assume that. You don't know which is the limiting reactant or which is present in excess, so you cannot calculate the concentration of the H2O2 that way at all.