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daniceko
Help? ill give medal :) Show your work Write a balanced net ionic equation for the following reaction. H3PO4(aq) + Ca(OH)2(aq) Ca3(PO4)2(aq) + H2O(l)
@kelly226 can you help
I'll help :) So you want to try and have the same number of each element on each side. This is a pretty tricky one. It looks like you have twice as many P on the right as on the left side. So try adding a 2 in front of H3PO4 on the left side as a starter!
This is really confussing for me so now i have 2 H3PO4(aq) + Ca(OH)2(aq) Ca3(PO4)2(aq) + H2O(l)
If you're REALLY confused, you should start with easier questions, this one's pretty tricky. So good now try the same thing with Ca. You have 3 Ca on the right and 1 on the left.
So would i put the 2 in front of the Ca like this? 2 H3PO4(aq) + 2Ca(OH)2(aq) Ca3(PO4)2(aq) + H2O(l) and btw there is no easier questions on the packet this is the only one like this
So: 2 H3PO4(aq) + 3Ca(OH)2(aq) -> Ca3(PO4)2(aq) + H2O(l) Now count your H's and O's on both sides and see if they're the same.
I think the Os are the same but are the Hs the same
So do it carefully. 2H3PO4 has 2*3 = 6 H and 2*4=8 O 3Ca(OH)2 has 3*2 = 6 H and 3*2 = 6 O So the left side has 14 O and 12 H Ca3(PO4)2 has 4*2 = 8 O H2O has 2H and 1 O So the right side has 9 O and 2 H So the right side has way less Os and Hs. Can you figure out how to balance that out?
In order to balance it out i have to add 5 o and 10 H some how right
Exactly! How can you get that?
could i add 5 to the H2O n the right end
Yes :) When you're adding 5 make sure you're adding 5 to 1. So the final thing should be 6H2O.
Yay :) so now I have 2 H3PO4(aq) + 3Ca(OH)2(aq) -> Ca3(PO4)2(aq) + 6H2O
That's the final answer! You can check it by counting everything of course. I started with P and Ca because they're only present in one of the compounds on each side, so they're easier to balance. Try to do the same when working on other problems.
Thank You so much your a genious :) But what about earlier when they were un equal bc of 5 o and 10 H I added the 5 ut what about the 10
Kinda hard to understand you there :P But you added 5 H2O. So you added 5*2=10 H and 5 O. Exactly what you needed.
Ok I understand now thank you so much for your help
That's what he wrote. Except an arrow instead of the = sign. It's a reaction, not an equation.
wait is there (aq) in the final equation?
@BluFoot is there (aq) in the final equation?
The states don't change when you balance the equation. So 2 H3PO4(aq) + 3Ca(OH)2(aq) -> Ca3(PO4)2(aq) + 6H2O (l) is correct