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Author Topic: CHEM AND BIO HELP AND TIPS HERE  (Read 357251 times)

Offline dlehddud

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Re: ~~~All Chemistry Doubts Here~~~
« Reply #150 on: November 11, 2009, 01:00:30 am »
Quote from: $!$RatJumper$!$ on November 10, 2009, 07:33:08 pm
guys .. what are all the equations u need to know for the production of sulphuric acid?

S + 02 --> SO2

2SO2 + O2 <--> 2SO3  (at 1atm. pressure, 450'C nd vanadium (V) oxide catalyst)

SO3 + H2SO4 --> H2S2O7

H2S2O7 + H2O --> 2H2SO4
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Offline buzywidbizworld

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Re: ~~~All Chemistry Doubts Here~~~
« Reply #151 on: November 11, 2009, 05:45:34 am »
Hello ppl,
i have this question from the Igcse chem guide topic11 on pgno.56.
For the followin redox reaction write half equations, showing the electron transfer. Then identify the change which is oxidation an the reactant which is the reducing agent. Give reasn for each ans.

i knw the answers n the 1st part of forming an equation is not the prob. i have a prob wid the 2nd part, i'm not able to understand the explaination given in the ans behind. It says I- is the reducing agent but i think it is wrong.

If u think the ans given is right then plz explain me.
Hope u got my question!!
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Offline @d!_†oX!©

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Re: ~~~All Chemistry Doubts Here~~~
« Reply #152 on: November 11, 2009, 06:58:29 am »
Hey buzywidbizworld

first of all the answer given at the back is right!
now the explanation:
the equation for Iodine is : 2I- - 2e- ---> I2
now as u can see the iodine is losing electrons and is thus oxidised(oil rig)
Whenever a substance is oxidised, it acts as a reducing agent
reason: because it is losing the electrons, which will later be gained by Cl to be reduced, therefore it is aiding Chlorine in getting reduced.
Do u get what i am trying to say?
Basically, always remember that whichever ion gets reduced acts as the oxidising agent and whichever gets oxidised acts as a reducing agent.

Tell me if you still didn't understand
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Offline ~~~~shreyapril~~~~

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Re: ~~~All Chemistry Doubts Here~~~
« Reply #153 on: November 11, 2009, 12:36:54 pm »
Write an ionic equation for the precipitation of the insoluble salt, silver(I) chloride.

answer this if ne body can!!!
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Offline @d!_†oX!©

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Re: ~~~All Chemistry Doubts Here~~~
« Reply #154 on: November 11, 2009, 12:37:49 pm »
dude i did it in the other thread!!!!!!!!!!!!y u posting the same question everywhere!??
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Offline ~~~~shreyapril~~~~

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Re: ~~~All Chemistry Doubts Here~~~
« Reply #155 on: November 11, 2009, 12:41:49 pm »
am in need of correct ans!!
so i am doidng tit everywhere!!

again someone!!

Write an ionic equation for the precipitation of the insoluble salt, silver(I) chloride
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Offline lastfashioned

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Re: ~~~All Chemistry Doubts Here~~~
« Reply #156 on: November 11, 2009, 02:10:20 pm »
she's such a charmer oh no
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Offline @d!_†oX!©

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Re: ~~~All Chemistry Doubts Here~~~
« Reply #157 on: November 11, 2009, 02:11:52 pm »
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Offline ~~~~shreyapril~~~~

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Re: ~~~All Chemistry Doubts Here~~~
« Reply #158 on: November 11, 2009, 02:14:47 pm »
Quote from: lastfashioned on November 11, 2009, 02:10:20 pm
she's such a charmer oh no
he is out of his mind!! :P
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Offline @d!_†oX!©

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Re: ~~~All Chemistry Doubts Here~~~
« Reply #159 on: November 11, 2009, 02:25:20 pm »
hey guys plss answer:

out of Scandium, Iron, Tin, and Mercury
why is Mercury the best oxidising agent agent and Scandium the best reducing agent?>?>?
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Offline buzywidbizworld

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Re: ~~~All Chemistry Doubts Here~~~
« Reply #160 on: November 11, 2009, 02:37:08 pm »
Quote from: @d!_†oX!© on November 11, 2009, 06:58:29 am
Hey buzywidbizworld

first of all the answer given at the back is right!
now the explanation:
the equation for Iodine is : 2I- - 2e- ---> I2
now as u can see the iodine is losing electrons and is thus oxidised(oil rig)
Whenever a substance is oxidised, it acts as a reducing agent
reason: because it is losing the electrons, which will later be gained by Cl to be reduced, therefore it is aiding Chlorine in getting reduced.
Do u get what i am trying to say?
Basically, always remember that whichever ion gets reduced acts as the oxidising agent and whichever gets oxidised acts as a reducing agent.

Tell me if you still didn't understand

Hey aditoxic!
Thanks alottt dude. I'm clear wid the ans nw. This concept of oxidation n reduction is tooo confusin for me but nw i hav got it.

once agn Thanks alot :)
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Offline @d!_†oX!©

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Re: ~~~All Chemistry Doubts Here~~~
« Reply #161 on: November 11, 2009, 02:38:43 pm »
ur welcome dude!!
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Offline Saladin

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Re: ~~~All Chemistry Doubts Here~~~
« Reply #162 on: November 11, 2009, 02:39:52 pm »
TO AADI

Oxidation is loss of electrons

Reduction is gain.

An oxidising agent will gain electrons in the process

A reducing agen will lose electron in the process

So scandium has the lowest number of electrons, so it will be more prone to lose them. Thus best reducing agent.

Mercury needs one more electron to make full shell, so will be more prone to gain electrons. Thus best oxidising agent.
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Offline ~~~~shreyapril~~~~

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Re: ~~~All Chemistry Doubts Here~~~
« Reply #163 on: November 11, 2009, 02:41:05 pm »
Quote from: @d!_†oX!© on November 11, 2009, 02:25:20 pm
hey guys plss answer:

out of Scandium, Iron, Tin, and Mercury
why is Mercury the best oxidising agent agent and Scandium the best reducing agent?>?>?
mercury is least reactive nd scandium the most!!
so whenever scandium reacts it reduces the others!!
and also when mercury reacts it takes up oxygel

like mercuryoxide+Mg=MErcury+MgO2!!!
samjha!!
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Offline @d!_†oX!©

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Re: ~~~All Chemistry Doubts Here~~~
« Reply #164 on: November 11, 2009, 02:42:08 pm »
thanks dude....and thanks shrey...samajh gaya!!!
By the way dude...its adi for adi_toxic not aadi...dts the other one
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