## anonymous one year ago Acid Base stoichiometry question

1. anonymous

23. In a chemical analysis, 25.0 ml of sulfuric acid was titrated to the second end point with 0.358 mol/L KOH. In the titration, an average volume of 18.2 ml was required. Calculate the molar concentration of the sulfuric acid.

2. anonymous

i have no idea where to start...

3. aaronq

first write an equation for the process

4. anonymous

so i put |dw:1433913881712:dw|

5. aaronq

That's not quite right. It says sulfuric acid and KOH, and if we include the side reactions with water, then, $$\sf H_2SO_4+2H_2O\rightarrow 2 H_3O^++SO_4^{2-}$$ $$\sf 2 H_3O^++SO_4^{2-}+2KOH\rightarrow K_2SO_4+4H_2O$$ If you cancel all the intermediates, the equation is: $$H_2SO_4+2KOH\rightarrow K_2SO_4+2H_2O$$ Now we need to find the moles of base. Use: $$\sf Molarity=\dfrac{moles_{solute}}{L_{solution}}$$