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HARD Half Equation

cl2+ naoh --> naclo3 + nacl +h20. I'm really struggling to do the half equation for this ;(. I know it's a disportionation reaction and i know the oxidation states of everything. It's just i got it wrong ;( PLZ help!
Reply 1
You mean the ionic equation?

Na+ + Cl- ==> NaCl all aqueous.
Reply 3
Original post by Xenon17
You mean the ionic equation?

Na+ + Cl- ==> NaCl all aqueous.


n0 but how did u get the ionic eq anyhow
Reply 4
Original post by Asad_2015
n0 but how did u get the ionic eq anyhow


For ionic equations, look at the product which is formed which is Nacl in this case, and form an equation using just the ions involved. Here, it will be the Na and Cl ions.

Na has a 1+ charge, and Cl has a 1- charge so they are aready balanced in terms of charges. So, we just form the equation:

Na+ + Cl- --> NaCl

For example now if the product was MgCl, then you would need 2 Cl ions as the Mg is a 2+ ions and you need to balance the charges:

Mg2+ + 2Cl- --> MgCl


For the half equation, what is the questions asking you to form the half equation for and from what? I'll go through it with you:smile:
Reply 5
Original post by derpz
For ionic equations, look at the product which is formed which is Nacl in this case, and form an equation using just the ions involved. Here, it will be the Na and Cl ions.

Na has a 1+ charge, and Cl has a 1- charge so they are aready balanced in terms of charges. So, we just form the equation:

Na+ + Cl- --> NaCl

For example now if the product was MgCl, then you would need 2 Cl ions as the Mg is a 2+ ions and you need to balance the charges:

Mg2+ + 2Cl- --> MgCl


For the half equation, what is the questions asking you to form the half equation for and from what? I'll go through it with you:smile:


that topic question half equation :s-smilie:
Reply 6
Moved to chemistry.
Consider each of the chlorine atoms separately

1) 1/2 Cl2 + e- ----> Cl-

2) The second one ends up in the chlorate ion - ClO3-


1/2 Cl2 ----> ClO3-

How would you go about balancing the second?

(Think about the NaOH)
Reply 8
Original post by Serine Soul
Consider each of the chlorine atoms separately

1) 1/2 Cl2 + e- ----> Cl-

2) The second one ends up in the chlorate ion - ClO3-


1/2 Cl2 ----> ClO3-

How would you go about balancing the second?

(Think about the NaOH)


how chlorate ions this is what i wasn't getting ;(
Original post by Asad_2015
how chlorate ions this is what i wasn't getting ;(


Think about the ions which made up each compound.

When we're doing simpler half equations, we usually have some oxygen atoms involved don't we?
Original post by Asad_2015
cl2+ naoh --> naclo3 + nacl +h20. I'm really struggling to do the half equation for this ;(. I know it's a disportionation reaction and i know the oxidation states of everything. It's just i got it wrong ;( PLZ help!


Do really mean half equation or are you just trying to balance this?

3Cl2 + 6NaOH ---> NaClO3 + 5NaCl + 3H2O
(edited 7 years ago)
Reply 11
Original post by TeachChemistry
Do really mean half equation or are you just trying to balance this?

Cl2 + 6NaOH ---> NaClO3 + 5NaCl + 3H2O


HALF equations
Reply 12
Original post by Serine Soul
Think about the ions which made up each compound.

When we're doing simpler half equations, we usually have some oxygen atoms involved don't we?


normally if its a compound we don't split it up in half equations :s-smilie: can u split up ionic compound only I'm not sure :frown:.

cause in MgO +Cu --> Mg + CuO

we say half eq is: mg2+ +2e--> mg

and cu --> cu2+ +2e-

but there there are half equations like mno3- --> mn

we say Mno3- +5e- +6h+ --> mn + 3h20 (we added water and h+ to balance the charge and atoms).

but like i split the compound at the top why can't we do the same and say

mn+5 +e- --> mn, like we did with magnesium :frown: I'm really confused on this part cause originally for naclo3 i just try to add that in the half equation but you split it up ? why :frown: and how do you know that clo3- forms a ion, why cudnt it not be 3/2o2- + cl-1?? i have this gap in my knowledge :frown: and i keep messing things up plz :tongue: help
Original post by Asad_2015
HALF equations


O.5Cl2 + 6OH- --> ClO3- + 3H2O + 5e-
Reply 14
Original post by TeachChemistry
O.5Cl2 + 6OH- --> ClO3- + 3H2O + 5e-


how ? :frown: you got that
Original post by Asad_2015
how ? :frown: you got that



You gave chlorate (V) in the original post so I just wrote the half equation for chlorine to that.
Reply 16
Original post by TeachChemistry
You gave chlorate (V) in the original post so I just wrote the half equation for chlorine to that.


how do u know when to split up chlorate? cause some formulae like Mno3- u don't split up,like how do u know what ions are formed :s-smilie: is there something i gotta learn ;(
Original post by Asad_2015
how do u know when to split up chlorate? cause some formulae like Mno3- u don't split up,like how do u know what ions are formed :s-smilie: is there something i gotta learn ;(


I do not understand what you have written here. You were the one who provide initial equation. I just broke it down into half equations like you asked.

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