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ionic equations

someone please give me a systematic method to deduce ionic equations
Reply 1
Bit strange you have no replies, they are different to normal equations in that you need to balance the charges as well. To do this you can use H+ OH- e- etc. There are some good videos on youtube if you are really stuck on it
ive never come across it like that at a-level. the only ionic equations ive come across have required me to just split the (aq) compounds into their ions and leave the solids as they are. then cancel the ions that appear on either side
Reply 3
Original post by user8937264980
ive never come across it like that at a-level. the only ionic equations ive come across have required me to just split the (aq) compounds into their ions and leave the solids as they are. then cancel the ions that appear on either side

My bad i read "deduce" as "balance"

Creator of this thread if you see this ignore what I said, aside from there are good youtube videos, I would say check out machemguy I remember struggling with ionic equations last year and he helped alot
Original post by samiul.tr
someone please give me a systematic method to deduce ionic equations


Ionic eqation is a matter of donating and accepting electrons. I would always look on the periodic table to see which of these elements attracts the electrons the most. In general elements which are close to the noble gases (or noble gases themselves!) have the greatest attraction and accept the electrons. Elements which are close to a new period donates the electrons. That is how I deduced such an equation.

Example:

chlorine is a noble gas, sodium in turn the first element in the third period. So chlorine attracts and accepts the electron on the outermost shell (valence shell) sodium donates:

2 Na -> 2 Na(+) + 2 e-
Cl2 + 2 e- -> 2 Cl-

2 Na(+) + 2 Cl- -> 2 NaCl

As Chlorine is a molecular gas, the equations have to be doubled!
(edited 10 months ago)

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