Question

what volume of butyric acid would be needed to make 25.0mL of a 1.0M solution?

Answer 1

I doubt that buryric acid is soluble enough in water to make a 1.0 M solution; however, as a problem it is done this way.
How many moles do you need? That is moles = M x L = ?
Then moles of the acid = grams/molar mass
Solve for grams; you have moles and molar mass.