Author Topic: Chemistry Help HERE ONLY !!  (Read 107354 times)

Offline sweetsh

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Re: Chemistry Help HERE ONLY !!
« Reply #600 on: May 31, 2009, 10:03:43 am »
can anyone give me list of:
1)soluble carbonates and the insoluble ones
2)insoluble alkalis, and soluble ones
3)soluble oxides and insoluble ones
4) amphotric oxides
I had a paper including all these but its lost :( Someone provide us with it

Offline aquarian93

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Re: Chemistry Help HERE ONLY !!
« Reply #601 on: May 31, 2009, 10:03:58 am »
hey wt is exactly the definition of "equilibrium" for reversible rxns? ???

Offline idol2009

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Re: Chemistry Help HERE ONLY !!
« Reply #602 on: May 31, 2009, 10:04:22 am »
Umm..okay..I'm not sure I really get it..
 I know that unsaturated compounds contain carbon-carbon double bonds, but none of these contain double bonds...
and you said that the formula for saturated compounds is CnH 2n+1, but aren't alkanes saturated compounds, and that's not their formula..right?
and alkenes are unsaturated and their formula is CnH 2n,

? i hope I haven't confused you and myself even more
=)

Offline Shogun

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Re: Chemistry Help HERE ONLY !!
« Reply #603 on: May 31, 2009, 10:07:27 am »
hey wt is exactly the definition of "equilibrium" for reversible rxns? ???

when the rate of forward and backward reaction is same, and their concentation of products and reactants does not change
one who masters both the pen and paper is indeed a true warrior.

\m/metal head\m/

Offline aquarian93

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Re: Chemistry Help HERE ONLY !!
« Reply #604 on: May 31, 2009, 10:08:11 am »
Umm..okay..I'm not sure I really get it..
 I know that unsaturated compounds contain carbon-carbon double bonds, but none of these contain double bonds...
and you said that the formula for saturated compounds is CnH 2n+1, but aren't alkanes saturated compounds, and that's not their formula..right?
and alkenes are unsaturated and their formula is CnH 2n,

? i hope I haven't confused you and myself even more

yea ur rite
alkanes fromula is CnH2n+2
alkenes is CnH2n
and yea alkanes are saturated

Offline Ghost Of Highbury

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Re: Chemistry Help HERE ONLY !!
« Reply #605 on: May 31, 2009, 10:08:44 am »
Alkalis are normally water soluble, although some like barium carbonate are only soluble when reacting with an acidic aqueous solution

i think all Group IA carbonates as in sodium carbonate, lithium carbonate etc. are soluble and the rest are insolube


divine intervention!

Offline Nano1313

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Re: Chemistry Help HERE ONLY !!
« Reply #606 on: May 31, 2009, 10:10:23 am »
all group 1 hydroxides and carbonates are soluble in water

Offline aquarian93

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Re: Chemistry Help HERE ONLY !!
« Reply #607 on: May 31, 2009, 10:13:43 am »
hey wt is exactly the definition of "equilibrium" for reversible rxns? ???

u guys, is equilibrium "when forward rxn is equal to the backward rxn" or the "conc. of reactant is equal to the products"

i dont get it :( pls help!

Offline godfather93

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Re: Chemistry Help HERE ONLY !!
« Reply #608 on: May 31, 2009, 10:15:04 am »
can anyone give me list of:
1)soluble carbonates and the insoluble ones
2)insoluble alkalis, and soluble ones
3)soluble oxides and insoluble ones
4) amphotric oxides

the richard harward book has all of this in a nice list.

Offline effigs

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Re: Chemistry Help HERE ONLY !!
« Reply #609 on: May 31, 2009, 10:15:41 am »
I believe both are the same-giant and macro

can u give me the exact question. w8 hybye said was right in a way. if your talking about giant covalent molecules then it's diamond, silica,graphite


germanium is an element so that is wrong
its not a question...i just need da meanings... ;D

sorry i was just loking through to see if there we stuff that would help me with my revision..and i came across ur doubt..
actually there is a very slight differnce between giant molecular covalents and macromolecular...
giant molecular covalents are very large numbers of (same) atoms bonded together to form on molecule with a very high relative molecular mass (for example, graphite, diamond, fullerenes (they are all different forms of carbon)
where as,
macromolecular are molecules with atoms of TWO (maybe more..im not quite sure) different elements in a giant covalent structure
hope that helped (Y)

Offline aquarian93

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Re: Chemistry Help HERE ONLY !!
« Reply #610 on: May 31, 2009, 10:18:30 am »
u guys,
for exothermic: we say the temp increases
and endothermic: the temp decreases

rite?

so this is abt the surrounding and not the reagent?

pls help!
When the reaction is endothermic.... The surroundings will cool down...e.g. the beaker may cool down....
When the reaction is exothermic..... the surrounding will heat up..... e.g. the beaker may heat up....
and yes...they are talking abt the surroundings....

@thukon ---->
Carbon comes after aluminium and before zinc...hope it helps


thanks!! :)

Offline aquarian93

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Re: Chemistry Help HERE ONLY !!
« Reply #611 on: May 31, 2009, 10:19:32 am »
hey wt is exactly the definition of "equilibrium" for reversible rxns? ???

when the rate of forward and backward reaction is same, and their concentation of products and reactants does not change

thanks :)
+rep

Offline Ghost Of Highbury

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Re: Chemistry Help HERE ONLY !!
« Reply #612 on: May 31, 2009, 10:19:56 am »
hey wt is exactly the definition of "equilibrium" for reversible rxns? ???

u guys, is equilibrium "when forward rxn is equal to the backward rxn" or the "conc. of reactant is equal to the products"

i dont get it :( pls help!
a time when the forward reaction rate and the reverse reaction rates are equal. The mixture is at equilibrium.
At equilibrium the numbers of reactant and product molecules stays constant. The identity of individual molecules keeps changing.
divine intervention!

Offline THEIGBOY

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Re: Chemistry Help HERE ONLY !!
« Reply #613 on: May 31, 2009, 10:23:00 am »
Umm..okay..I'm not sure I really get it..
 I know that unsaturated compounds contain carbon-carbon double bonds, but none of these contain double bonds...
and you said that the formula for saturated compounds is CnH 2n+1, but aren't alkanes saturated compounds, and that's not their formula..right?
and alkenes are unsaturated and their formula is CnH 2n,

? i hope I haven't confused you and myself even more

No...no....i'm not confused or anything,..The formula I gave you was only for the end of a FAT CHAIN...to check whether it is a saturated or unsaturated FAT....Alkanes and alkenes DO have a separate general formula.....
What i was saying was about fats ONLY... that formula is ONLY for the END of a FAT chain....
Please tell me if u get it...
« Last Edit: May 31, 2009, 10:25:30 am by THEIGBOY »

Offline Shogun

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Re: Chemistry Help HERE ONLY !!
« Reply #614 on: May 31, 2009, 10:36:52 am »
hey wt is exactly the definition of "equilibrium" for reversible rxns? ???

when the rate of forward and backward reaction is same, and their concentation of products and reactants does not change

thanks :)
+rep

ure welcome thanx for the rep  ;D
one who masters both the pen and paper is indeed a true warrior.

\m/metal head\m/