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half equations (1 Viewer)

HiHaii

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do you need to do reduction or oxidation to the spectator ion shown?

and is there is a last step i.e. removing the spectator electrons coming out to be



and

 

ibbi00

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For Ba + HCl acid



1st one needs to be balanced.

EDIT: If I was to balance it, it would be:




And the net ionic equation would be:


And of course you need to add the states if you don't wana lose marks.

Correct me if I'm wrong.
 
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adomad

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if there are no states, the HSC assumes that its aq, especailly when ur doing ionic equations
 

ibbi00

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if there are no states, the HSC assumes that its aq, especailly when ur doing ionic equations
Ah allright cool. One noob question though. How were you able to determine the spectator ion in the second reaction?
 
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ibbi00

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Write out a full ionic equation, and the speciies which is the same on both sides of the equation is a spectator.
Yea but I usually do my ionic equations after determining spectators and In this case I based it on adomad's one
 
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hscishard

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I don't get it. What is the purpose of ionic equations?

Initially I thought it was to find the ionic compound, but it's not.
 

MetroMattums

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I don't get it. What is the purpose of ionic equations?

Initially I thought it was to find the ionic compound, but it's not.
It's to determine the movement of electrons - it'll come up a lot next year for you so get accustomed to it ;D
 

MetroMattums

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Well..that makes sense for the half equations.

But the cancelling of the spectator ions makes everything weird
How so? The spectator ions don't interact with the reactants or products in terms of electron transfer - that's why they're ignored in the net ionic equation.
 

hscishard

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How so? The spectator ions don't interact with the reactants or products in terms of electron transfer - that's why they're ignored in the net ionic equation.
My teacher hasn't gone in depth about this.

Why would we cancel out, if it is necessary for it to form Aluminium sulfate?
 

iRuler

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My teacher hasn't gone in depth about this.

Why would we cancel out, if it is necessary for it to form Aluminium sulfate?
They basically sit there and "watch" the reaction to make it easier.
 

mirakon

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in other words the transfer of electrons in redox reactions excludes the spectator ions, so they are unnecessary in the redox half-equations.
 

hscishard

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Okay. I get that now.

Now can ionic equations be formed with anything? Like E.G. 2H20<-->2H2+02.
Or is it only applicable for equations that have aqueuous states.
 

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