Balancing Equations
Al+N2-->AlN
NH4NO3-->N2O+H2O
Pb(NO3)2+HCl-->PbCl2+HNO3
Are you balancing these by inspection or by redox methods? I assume by inspection this early in the course. I will do the first one and you do the others.
Al + N2 ==> AlN
Rule 1. You may NOT change any of the subscripts. You MAY change coefficients ONLY.
By inspection, we can see Al is balanced and N is not. We can balance N by placing a 2 for AlN. Like so.
Al + N2 ==> 2AlN
Of course that messes up the Al but we can fix that by placing a 2 on the left for Al. Like so.
2Al + N2 ==> 2AlN
Now, we ALWAYS check it to make sure it is balanced. I see 2 Al on the left and 2 Al on the right. OK.
I see 2 N on the left and 2 on the right. OK.
So, it's balanced.
Now you do the others. I shall be happy to check your work. Start the the last one. That's a little easier than #2.
Pb(NO3)2+HCl-->PbCl2+HNO3
Pb(NO3)2+2HCl-->PbCl2+HNO3
I'm not sure. Long ones are a bit more difficult.
You can ALWAYS tell if your answer i correct by checking it.
I see 1 Pb on the left and 1 on the right. OK>
I see 2 N on the left and 1 on the right. NO GO. We can stop there becasue we know it isn't balanced. Howver, H doesnt balance either for there are 2 on the left and 1 on the right. Oxygen has 6 on the left and 3 on the right. With Pb and Cl OK, that just leaves you to fix the HNO3 so it balances H, N and O all at the same time.
So would HNO3 become 3HNO?
Rule #1. You may NOT change any subscripts. You MAY change ONLY coefficients.
I have no idea then.. I'm lost.
You can't be lost. You are so CLOSE it would bite if it could.
Let's go over it bit by bit.
There is 1 Pb on the left and 1 on the right so that is OK.
There are 2 Cl on the left and 2 on the right. That is OK. You had to place a 2 in front of the HCl so the Cl would balance. That's great. So what's left.
You look on the right and the H atoms don't balance. You now have 2 on the left so put a 2 in front of the HNO3. That will take care of the H atoms for we now have 2 on the left (from 2HCl) and 2 on the right (from 2HNO3). That leaves N and O so we check them out.
You have 2 N on the left (from Pb(NO3)2) and 2 on the right (from 2HNO3). N is OK. What about O. We have 6 O on the left (from Pb(NO3)2) and we have 6 O on the right (from 2HNO3). Done. All you needed to do was balance the H and everything else fit into place.
Oh thank you! You were a bunch of help.
Do you want to do the middle one. It's easy. Balance N first. Balance H next. Balance O last.
Yeah, easy for you to say! ;(
NH4NO3-->N2O+H2O
2N 2(H4)2?NO3-->2NO+H2O
I tend to overthink a lot...I make it harder than it seems.