## wolfgirl 3 years ago In the equation ___CH4 + ___O2 ___CO2 + ___H2O, what number will go in front of the H2O to balance the equation?

1. online334

idk that is hard lol

2. JamesJ

I guess what you mean is ___CH4 + ___O2 --> ___CO2 + ___H2O is that right?

3. wolfgirl

yes

4. online334

yeah i was going tay what james said

5. online334

lol

6. online334

hi james it is snowball

7. online334

i got banned made another acount thoe

8. JamesJ

well the number of atoms of each element has to balance on both sides. So if we start with one CH4 atom, we must have one CO2 atom: 1 CH4 + ___O2 --> 1 CO2 + ___H2O Now, what can you say about the other two atoms? (Hi online/snowball)

9. online334

hi james

10. wolfgirl

that there are a 2 of them

11. online334

yeah

12. JamesJ

Did you see why with one CH4 molecule there must be one CO2 molecule? That is because with one CH4 molecule, there is only one carbon atom on the left-hand side. So there must only be one carbon atom on the right-hand side.

13. wolfgirl

ok. I understand

14. online334

good

15. JamesJ

So right now we have that 1 CH4 + ___O2 --> 1 CO2 + ___H2O Now, given that, how many hydrogen atoms must there be on the RHS (right hand side)?

16. wolfgirl

4?

17. JamesJ

Yes. And hence how many water molecules H2O must there be?

18. wolfgirl

4

19. JamesJ

No. Each water molecule has two hydrogen atoms, that's why we write H2O and not HO

20. wolfgirl

so it's 2?

21. online334

yes

22. JamesJ

Yes. Hence we now have that 1 CH4 + ___O2 --> 1 CO2 + 2 H2O Now, count up the oxygen atoms on the RHS and figure out how many O2 molecules we need on the LHS.

23. wolfgirl

2

24. online334

omh lhs iw my highschool i use to go to

25. JamesJ

right. So the final answer is 1 CH4 + 2 O2 --> 1 CO2 + 2 H2O

26. wolfgirl

ok thank you

27. online334

no problem

28. JamesJ

You can see that there are some more questions like this here; scroll down a bit. You might find it useful to have a look at them.

29. wolfgirl

ok. I will