A few chemistry questions basically proportion calculations

1. Jan 21, 2013

lionely

1. The problem statement, all variables and given/known data

Chloroethane, reacts with Oxygen according to the equation below:
2C2H3Cl + 5O2 → 4CO2 + 2H2O
+2HCl
How many moles of CO2 are produced when 3.0 moles of choloroethane and 3 mol of O2 are reacted?

When 50cm3 of 1mol/dm3 HCl is mixed with 50cm3 of 1mol/dm3 NaOH, the temp of the resulting solution increases by 6 °C. What will be the temp change when 100cm3 of each of these solutions are mixed?

I'm sorry I don't really have any idea on how to attempt these properly, could you guys give me a hint? Please!!! The help would be greatly appreciated !!

2. Jan 21, 2013

Staff: Mentor

3. Jan 21, 2013

lionely

So for the first one it is 5mole of Oxygen gives 4 mole of CO2? so
3mole of Oxygen gives X moles?

4. Jan 21, 2013

Staff: Mentor

Yes, but you have to check if there is enough chloroethane to react with 3 moles of oxygen. Could be there is not enough, then you will have to calculate amount of CO2 knowing that 2 moles of chloroethane produce 4 moles of carbon dioxide.

This is so called limiting reagent problem.

5. Jan 21, 2013

lionely

So is it 2 moles of chloroethane react with to produce 4 mole of carbon dioxide
so 3moles gives x?

6. Jan 21, 2013

Staff: Mentor

Yes.

7. Jan 21, 2013

lionely

So the overall answer is 6moles of CO2?

8. Jan 21, 2013

Staff: Mentor

How many moles of CO2 would be produced from 3 moles of O2?

9. Jan 21, 2013

2.4moles