Chemical Forums
Chemistry Forums for Students => Undergraduate General Chemistry Forum => Topic started by: XenoCham on October 25, 2006, 07:17:49 PM
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I am sorry. I am not doing so well in General Chemistry, as I thought I was going to do. I took Physiological Chemistry and loved it, so I registered for Gen Chem, and it's hard. :-\
But, here's a question that I hope you guys can't help me out with. I would greatly appreciate it.
I did most of the work, but the last part stumpped me. I do not know what they are asking for.
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4KCl + 4 HNO3 + O2 ------> 4 KNO3 + 2 Cl2 + 2 H2O
Calculate the mass of KCl requiered to produce 567g of potassium nitrate.
What mass of chlorine is generated as well?
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I got :
567g KNO3 x 1 mol KNO3 / 101.11g KNO3 = 5.62 mol KNO3
5.62 mol KNO3 x 74.55 KCl / 1 mol KNO3 = 418g KCl
I got the mass for KCl, but I don't know what to do from there to get the mass for Cl.
I'm sorry, I hope that you guys that help me out on this one. I really appreciate it again.
take care ^_^
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4KCl + 4 HNO3 ------> 4 KNO3 + 2 Cl2 + 2 H2O
Can you check this equation? It isn't balanced, and looks really odd to me.
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I'm sorry, you are right.
This is the right way
4 KCl + 4 HNO3 + O2 -------> 4 KNO3 + 2 Cl2 + 2 H2O
thank you for noticing that.
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OK, yeah that makes sense now
1) How many moles of KCl do you have? We will call this number "n"
2) so how many moles of Cl- do you have?
3) How many Cl2 molecules are formed by one ion of Cl-? hint: it's not a whole number
4) So how many moles of Cl2 molecules are formed by one mole of Cl-?
5) So how many moles of Cl2 molecules are formed by "n" moles of Cl-? We will call this number of moles "m"
6) what is the mass of "m" moles of Cl2?