half equations (1 Viewer)

HiHaii

Member
Joined
Aug 16, 2009
Messages
63
Location
Campsie
Gender
Male
HSC
2011
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

Member
Joined
Sep 6, 2009
Messages
771
Gender
Male
HSC
2010





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.
 
Last edited:

adomad

HSC!!
Joined
Oct 10, 2008
Messages
543
Gender
Male
HSC
2010
if there are no states, the HSC assumes that its aq, especailly when ur doing ionic equations
 

ibbi00

Member
Joined
Sep 6, 2009
Messages
771
Gender
Male
HSC
2010
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?
 
Last edited:

ibbi00

Member
Joined
Sep 6, 2009
Messages
771
Gender
Male
HSC
2010
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
 
Last edited:

hscishard

Active Member
Joined
Aug 4, 2009
Messages
2,033
Location
study room...maybe
Gender
Male
HSC
2011
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

Member
Joined
Apr 29, 2009
Messages
233
Gender
Male
HSC
2010
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

Member
Joined
Apr 29, 2009
Messages
233
Gender
Male
HSC
2010
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

Active Member
Joined
Aug 4, 2009
Messages
2,033
Location
study room...maybe
Gender
Male
HSC
2011
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

Premium Member
Joined
Oct 13, 2008
Messages
6,731
Location
3.141592654
Gender
Male
HSC
2010
Uni Grad
2014
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

nigga
Joined
Sep 18, 2009
Messages
4,222
Gender
Male
HSC
2011
in other words the transfer of electrons in redox reactions excludes the spectator ions, so they are unnecessary in the redox half-equations.
 

hscishard

Active Member
Joined
Aug 4, 2009
Messages
2,033
Location
study room...maybe
Gender
Male
HSC
2011
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.
 

Users Who Are Viewing This Thread (Users: 0, Guests: 1)

Top