Okay I'm stuck in South Korea where I can't find any chemistry books and this question is driving me nuts!! Can someone please help?

Chlorine dioxide, ClO2, has been used as a disinfectant in air conditioning systems. It reacts
With water according to the reaction:
ClO2 + H2O ---> HClO3 + HCl
If 142.0 g of ClO2 is mixed with 38.0 g of H2O, how many grams of which reactant remain
After the reaction is over

do you know about moles?

The number of moles is proportional to the balancing in the equation, so from your equation, 1 mole of ClO2 and 1 mole of H2O will form 1 mole of HClO3 and 1 mole of HCl.

You need to work out how many mole of the reactants you have, and work out which one is less, then you can work out how many moled of the products will be produced, and then convert that back to mass to answwer your question.

Please ask if you have trouble understanding this :)

This question would be much easier if it were in solution...

It's pretty easy...

I understand the concept but I'm still pretty useless could you maybe please help me out a bit more. It's the last question on my assignment and I'm struggling like an idiot. Thanks I would really appreciate it. If there's any chance that you would please look through my answers on my assignment would you? I'm new at chemistry and have no books but I will kick you'll see..

Haha, I don't have the time myself, And I'm a bit rusty at chemistry, maybe kp or rudi_in whill offer their services... we'll see.

For this one, you need to work out the molecular weights, so for H2O the molecular weight is 16+1+1 (O+H+H using atomic mass) which is 18. This means that 18 grams is 1 mole of H2O. You have 38g, so you can work out how many moles you have.

When you;ve done this for Chlorine dioxide too, you can see which one you have the least moles of, this will be your limiting reactant. This is the number of moles of EACH PRODUCT you will form, from there you can work out how many grams of each product you have using molecular weights.

I got it!! Thanks man!! Damn it feels good!

You get that tingle in your brain? Ooh yeah! :p