## zaphod 3 years ago 25 cm^3 of 2mol/dm^3 Sodium hydrixude solution and 25cm^3 of 2 mol/dm^3 Sulphuric acid were mixed well to make a solution X. Calculate the concentration of Sulphuric acid in the final solution..

1. zaphod

@Callisto @TuringTest

2. Callisto

Sodium hydroxide?

3. zaphod

h2so4?

4. Callisto

Do you mean sodium hydroxide for ''Sodium hydrixude''?

5. zaphod

yh

6. Callisto

Can you write the chemical equation for the reaction first?

7. zaphod

2NaOH + H2SO4 ---> Na2SO4 + 2H20

8. Callisto

In this reaction, what is the limiting agent?

9. zaphod

limiting agent means? i found the answer it is 1 moldm^-3 cn u check it

10. Callisto

Hmm, I didn't get the same answer as you.

11. zaphod

can u shw ur working

12. Callisto

Perhaps I didn't do it correctly, since I haven't studied chemistry for quite a long time.. No. of mole of H2SO4 used = 1/2 (no. of mole of NaOH) = (1/2) (2x25/1000) = x *NaOH is the limiting agent that will be used up in the reaction. No. of mole of H2SO4 left = no. of mole of H2SO4 - no. of mole of H2SO4 used = (2x25/1000) - x = y Concentration of H2SO4 in the final solution = no. of mole of H2SO4 left / volume of the solution. And I take volume of the solution remains unchange, that is 25cm^3 + 25cm^3 = 50cm^3 Did I do anything wrong?

13. zaphod

This is how i did, check if im wrong 2NaOH + H2SO4 ---> Na2So4 +2 H20 the molar ratio is tht, 2 moles of NAOH reacts with 1 mole of H2so4 when u calculate the number of moles in each reactnt it is 0.05 mole, which means 0.05 mol of Naoh react with 0.025 mol of H2so4...so there is 0.025 mole of H2so4 left n = c*v/ 1000 0.025 = c * 25/1000 c = 1 mol dm^-3

14. Callisto

Why is it 25cm^3 for your volume?

15. zaphod

should it be 50 or 25?

16. zaphod

im not sure of this

17. Callisto

Hmm.. final solution, it's not just the volume of H2SO4, so I prefer using the total volume. But I'm not sure though. As I've said, I haven't studied chemistry for quite a long time!

18. zaphod

then the answer becomes 0.5 moldm^-3

19. Callisto

That's what I got. Sorry for the late reply

20. zaphod

so my method is right?

21. Callisto

The method is right, just the volume is not right/

22. zaphod

thanks alot :)

23. Callisto

Welcome :)