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# AS chemistry - post here if need help watch

1. how immature r ppl in this forum?
2. (Original post by z!D4N)
dude, u still said sth related how wise u r. that doesnt make a difference.

followed by lol, it was a joke.......so lay off.....capiece!
3. (Original post by KOH)
Great every one has the same answer as my book does, anyone wanna share how they got it?

Ok.. ignore the equation with the NO first

take the hess's law cycle

4HN3+3O2 -------------> 2N2+6H2O

6H2+3O2+2N2

Since N2 is from their element change from N2 to N2 and O2 to O2 is 0 so u can ignore that.. you know the enthalpy of formation for water is -576KJ per TWO moles of water.. so that means -288KJ for one mole.
To get from bottom to the top right, times the -288 by 6 because 6 moles of water.

From that you know the enthalpy change for the top equation is -1530. Since you are going backwards it's +1530. So you get -1728 and +1530 to get to 4HN3+3O2. but O2 is 0 so that means the enthalpy change must be of the ammonia. Then you jus simply divide=198 by 4
4. (Original post by KOH)
followed by lol, it was a joke.......so lay off.....capiece!
dude, jus because u realized that, u say it was a joke.

OKay.
5. (Original post by z!D4N)
how immature r ppl in this forum?
you right!! we are all stupid, wrong, immature, dumb, your the dominant life form, goddish, smart,
6. (Original post by z!D4N)
dude, jus because u realized that, u say it was a joke.

OKay.

DUDE, you gotta get ur head checked out, u gotta a serious social prob! have to make enemies with everyone!
7. (Original post by KOH)
what the heck does that mean>

It means he add me to his ignore list and dun wanna see my messages because i whooped his ass and knows too many secrets about his sad loner life
8. (Original post by KOH)
you right!! we are all stupid, wrong, immature, dumb, your the dominant life form, goddish, smart,
how sarcastic. but u guys r not very open-minded for goodness sake.
9. (Original post by daydream)
Ok.. ignore the equation with the NO first

take the hess's law cycle

4HN3+3O2 -------------> 2N2+6H2O

6H2+3O2+2N2

Since N2 is from their element change from N2 to N2 and O2 to O2 is 0 so u can ignore that.. you know the enthalpy of formation for water is -576KJ per TWO moles of water.. so that means -288KJ for one mole.
To get from bottom to the top right, times the -288 by 6 because 6 moles of water.

From that you know the enthalpy change for the top equation is -1530. Since you are going backwards it's +1530. So you get -1728 and +1530 to get to 4HN3+3O2. but O2 is 0 so that means the enthalpy change must be of the ammonia. Then you jus simply divide=198 by 4
thanks, your loads alot usefull than z!dan .....would give ya rep, but ran out for today!! lol

thnx anyway dude,,,i owe ya one! ANYTIME
10. (Original post by KOH)
DUDE, you gotta get ur head checked out, u gotta a serious social prob! have to make enemies with everyone!
dude, this is only a forum, i dont care. its jus that they dont agree with me.
11. (Original post by KOH)
thanks, your loads alot usefull than z!dan .....would give ya rep, but ran out for today!! lol

thnx anyway dude,,,i owe ya one! ANYTIME
daydream's a Dr. u know
12. (Original post by daydream)
It means he add me to his ignore list and dun wanna see my messages because i whooped his ass
correction; thats 2 i owe ya. thanks for whoopinf his ass dude, he needs it!
13. (Original post by z!D4N)
daydream's a Dr. u know
is that true>?

than that proves how stupid you are, trying to challenge a dr.??? jeez!
14. (Original post by KOH)
correction; thats 2 i owe ya. thanks for whoopinf his ass dude, he needs it!
-_-' nice self-satisfaction.
15. (Original post by KOH)
is that true>?

than that proves how stupid you are, trying to challenge a dr.??? jeez!
he got pissed before
16. i now understand why ppl get such low grades.
17. (Original post by z!D4N)
he got pissed before
surely not by someone like YOU!
18. I never said i was a doctor? but it's cool to get praized by someone which thinks i'm a doctor haha
19. (Original post by KOH)
surely not by someone like YOU!
LOL. ur pretty shallow.
20. does anyone know how to get past papers for OCR Salters i can find the specimen papers and i know that they have changed the sylabus.<-- is that spelt right?? anywho,can you help??

strip
xx

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