precipitation help please

[HoangDDS]

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Besides understanding that Q>K causes precipitation. How do I know just by the given choices what forms a solid in aqueous solution?

which will not yield a precipitate?
a) AgNO3 + KBr
b) Pb(NO3)2 + KCl
c)NaNO3 +NH4Cl
d) BaBr2 + Na2SO4
e) CaI2 + (NH4)2CO3

Thanks!!!!!!!

 

[Maygyver]

I think you just need to memorize the little chart of common soluble solutions.

 

[osimsDDS]

here check this out, memorize this and your set for ANY solubility question they throw at you...

http://members.tripod.com/~EppE/soluble.htm

The answer should be C:

NaNO3 +NH4Cl, because NaCl and NH4(NO3) are both soluble and will not form precipitates

trust me memorize that link i gave you and your golden its easy...

 

[TeamGuo]

Besides understanding that Q>K causes precipitation. How do I know just by the given choices what forms a solid in aqueous solution?

which will not yield a precipitate?
a) AgNO3 + KBr
b) Pb(NO3)2 + KCl
c)NaNO3 +NH4Cl
d) BaBr2 + Na2SO4
e) CaI2 + (NH4)2CO3

Thanks!!!!!!!

It's just solubility rules. and the answer is c. group I and NH4+ compounds are always soluble.

 

[HoangDDS]

Thanks guys. And thanks Osims for that link.

I eliminated A and B off the bat, but I got stuck after that.

Dude, is it just me or there's a **** load of ions to memorize?

The only solubility rule that I got down are:
1) all group 1 metals and NO3 and NH4 are soluable (except (NH4)2SO4)
2) most Ag, Pb, Hg are insoluable

but that's it. Thanks anyways. I guess I'll try my best to memorize this http://members.tripod.com/~EppE/soluble.htm

 

[osimsDDS]

the best rule to remember if ANYTHING is just that alkali metals and NH4+ are soluble with any molecule...but again just try to memorize the whole thing while your at it...i just looked at it every morning when i woke up and before i went to bed and it stayed with me. I thought it was bad but you start grouping things together and ordering them after a while at looking at it...

 

[HoangDDS]

the best rule to remember if ANYTHING is just that alkali metals and NH4+ are soluble with any molecule...but again just try to memorize the whole thing while your at it...i just looked at it every morning when i woke up and before i went to bed and it stayed with me. I thought it was bad but you start grouping things together and ordering them after a while at looking at it...

Now that's dedication. Thanks for the tip and good luck Friday bro.

 

[osimsDDS]

Now that's dedication. Thanks for the tip and good luck Friday bro.

thanks ill need it