Author Topic: Chemistry Help needed!:-(  (Read 13253 times)

Offline Naruto

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Chemistry Help needed!:-(
« on: May 01, 2009, 02:33:53 pm »
hello
Can anyone tell me how to make an ionic equation?

And what will be the ionic equation of the following:-

1) 2NaOH + H2SO4 ---> Na2SO4 + 2H2O

2) CuSO4(aq) +2NaOH(aq) ---> Cu(OH)2(s) + Na2SO4(aq)

3) MgCO3 + H2SO4 ---> MgSO4 + H2O + CO2

Offline emi

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Re: Chemistry Help needed!:-(
« Reply #1 on: May 01, 2009, 02:48:40 pm »
if its an alkali reacting with strong acid the ionic equation will be

OH(negative)+H(positive)-----> H2O
this one is for the first one

im not sure about the rest ,  but here is one more thing

ionic equation for any ammonium salt reacting with alkali  is -->
NH4(+) + OH(-) -----> NH3+H2O



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Offline Naruto

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Re: Chemistry Help needed!:-(
« Reply #2 on: May 01, 2009, 02:57:53 pm »
Thanks emi :) so you mean that for a particular reaction ( like acid reacting with metal) the ionic equation will always be the same.. no matter what the reactants are?

And can anyone help me out with the rest of the equations and tell me the way to work out the ionic equation... i would be grateful.
Thanx

Offline hyebyekadal

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Re: Chemistry Help needed!:-(
« Reply #3 on: May 01, 2009, 03:06:40 pm »
im not so sure of ammonium and alkali...
hm...

Offline emi

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Re: Chemistry Help needed!:-(
« Reply #4 on: May 01, 2009, 03:17:34 pm »
yes for strong alkali + strong Acid the ionic Equation will always be the same  which is
OH(negative)+H(positive)-----> H2O

same goes for the ammonium salts reacting with alkali
NH4(+) + OH(-) -----> NH3+H2O
« Last Edit: May 01, 2009, 03:37:00 pm by emi »
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Offline hyebyekadal

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Re: Chemistry Help needed!:-(
« Reply #5 on: May 01, 2009, 03:48:15 pm »
in inoic equation take only that change state OR thier bondinfg
1.OH(-)+H(+)=H2O
2.Cu(2+)+OH(-)=Cu(OH)2
3.2H(+)+CO3(2-)=H20+CO2

Offline Naruto

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Re: Chemistry Help needed!:-(
« Reply #6 on: May 02, 2009, 04:07:53 pm »
@ hyebyekadal
Can you tell me that why in your answer to number 3 there are 2H+ ions????
plzzzz tell me bcuz this was the main reason why i wrote these equations...

Offline Naruto

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Re: Chemistry Help needed!:-(
« Reply #7 on: May 02, 2009, 04:14:31 pm »
Okay hyebyekadal is not online so can anyone else tell me...plzzzzz :(

Offline astarmathsandphysics

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Re: Chemistry Help needed!:-(
« Reply #8 on: May 02, 2009, 04:43:15 pm »
The equations have to balance for the charges. In equation 2 there should be 2 OH(-)

Offline Naruto

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Re: Chemistry Help needed!:-(
« Reply #9 on: May 02, 2009, 04:51:37 pm »
If we have to balance it then why in equation 1 its not 2H+?

Offline astarmathsandphysics

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Re: Chemistry Help needed!:-(
« Reply #10 on: May 02, 2009, 05:09:09 pm »
1 - cancels 1+

Offline Naruto

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Re: Chemistry Help needed!:-(
« Reply #11 on: May 02, 2009, 05:20:21 pm »
ummm...i thought that bcuz there are 2 hydrogen atoms on left side and 2 on right side thats why its not 2H+?
OH- + H+ ---> H2O

Offline godfather93

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Re: Chemistry Help needed!:-(
« Reply #12 on: May 02, 2009, 05:23:28 pm »
yup, what you just said is right!

Offline Naruto

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Re: Chemistry Help needed!:-(
« Reply #13 on: May 02, 2009, 05:38:32 pm »
hey guyz thanks for answering my question it had cleared my confusion, but i have some for question....hope you will answer them in a same way:)

Q: which is more accurate 'burette' or 'pipette' or 'measuring cylinder' ?

Q: What is the maximum range of all these three insturments?

Q: And sometime in the exam they give us a situation like..... '25 cm3 of acid is used, so which insrtument will be used to give an accurate measurement?

thanx:):)

Offline hyebyekadal

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Re: Chemistry Help needed!:-(
« Reply #14 on: May 02, 2009, 06:05:57 pm »
lol i need help in that too but i no pipette more acccurat thatn measuring cylinder.. also
OUt of this topic sorry but can anyone whos really good at IGCSE physics tell me how to prepare for p6??
I mean we never did like any experiment at school. Because um..  my teach is ,,um ahem//
nvm so can anyone tell me any good other site or something? my 1rst exam is p6 phy and on may 12th.
i hv study guide and tom duncan IGCSE phy...
so Thank You in advance!