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Why is the chemical formula of sodium nitrate(III) equals NaNO2? Does it have something to do with the oxidation numbers? Please help me
Original post by Cookieesss
Why is the chemical formula of sodium nitrate(III) equals NaNO2? Does it have something to do with the oxidation numbers? Please help me


sodium nitrate III formula is NaNO3
Original post by Charliewiz
sodium nitrate III formula is NaNO3


is it?

the "III" refers to Nitrogen, so Nitrogen is 3+
Na is 1+
so to balance out the overall 4+ charge surely you'd need 2 O's to give you a 4- charge to make the compound neutral?

So it'd be NaNO2
no?

or do you not know and you just plucked the answer off of google?
Original post by hamzakalinle
is it?

the "III" refers to Nitrogen, so Nitrogen is 3+
Na is 1+
so to balance out the overall 4+ charge surely you'd need 2 O's to give you a 4- charge to make the compound neutral?

So it'd be NaNO2
no?

or do you not know and you just plucked the answer off of google?


Wait im not sure now. Ive looked on the internet and theres varying answers between NaNo3 and NaNo2
Original post by Charliewiz
Wait im not sure now. Ive looked on the internet and theres varying answers between NaNo3 and NaNo2


yeah I'm 99% sure its NaNO2; it's prolly because sodium nitrate III has it's own name and google is bringing up NaNO3 because that's the actual Sodium Nitrate.

I'm pretty sure Sodium Nitrate III goes by the name of Sodium Nitrite or something
Original post by Cookieesss
Why is the chemical formula of sodium nitrate(III) equals NaNO2? Does it have something to do with the oxidation numbers? Please help me


alright OP, you're 100% correct it has everything to do with oxidation numbers.

Na = +1 charge, we know this because Sodium is in group 1 (in the new specs you may see it refered to group 11 but they're the same thing)
N= +3, we know this because of the Roman Numeral III in the name

so overall, we have a +4 charge.

Oxygen has a -2 charge, so to balance out the 4+ charge we need 2 Oxygens to make the compound neutral.

thus, NaNO2.
Reply 6
Original post by hamzakalinle
is it?

the "III" refers to Nitrogen, so Nitrogen is 3+
Na is 1+
so to balance out the overall 4+ charge surely you'd need 2 O's to give you a 4- charge to make the compound neutral?

So it'd be NaNO2
no?

or do you not know and you just plucked the answer off of google?


Thank you! But why is sodium nitrate (V) equals NaNO3?
Reply 7
Original post by hamzakalinle
alright OP, you're 100% correct it has everything to do with oxidation numbers.

Na = +1 charge, we know this because Sodium is in group 1 (in the new specs you may see it refered to group 11 but they're the same thing)
N= +3, we know this because of the Roman Numeral III in the name

so overall, we have a +4 charge.

Oxygen has a -2 charge, so to balance out the 4+ charge we need 2 Oxygens to make the compound neutral.

thus, NaNO2.


Thank you! But why is sodium nitrate (V) equals NaNO3?
Oxidation number of Na= +1
Oxidation number of N= -3 (because of the roman numeral)
Oxidation number of NO3= -1

Shouldn't the chemical formula be NaNO?
Yep as stated above, III refers to nitrogen. If it referred to sodium it would've been sodium (III) nitrate.

Oxygen -2
Sodium +1
Therefore to balance the equation zero as it has no charge, nitrogen must be +3 therefore Nitrate(III)
Original post by Cookieesss
Thank you! But why is sodium nitrate (V) equals NaNO3?
Oxidation number of Na= +1
Oxidation number of N= -3 (because of the roman numeral)
Oxidation number of NO3= -1

Shouldn't the chemical formula be NaNO?



V=5
3 oxygens = -6 charge
Na= +1 charge
Nitrogen must equal +5 charge to make it 0 overall

Charge of oxygen is always -2 and sodium always +1 unless stated otherwise, nitrogen is the variable that's why it's NaNO3, N changes from +3 from the earlier question to +5, it's being oxidised
(edited 6 years ago)
Original post by Cookieesss
Thank you! But why is sodium nitrate (V) equals NaNO3?
Oxidation number of Na= +1
Oxidation number of N= -3 (because of the roman numeral)
Oxidation number of NO3= -1

Shouldn't the chemical formula be NaNO?


okay so the Roman Numeral V means 5, have a look at Roman Numerals because they're commonly used in A Level Chem, and it refers to the Nitrogen.

Why? - because we already know Na is +1 always and that Oxygen is +2 always (unless it's in a peroxide, which in this case, it isn't) so it can only be referring to Nitrogen.

So; Na= +1 like you said
N= +5 because of the Roman Numeral
overall we have a plus 6 oxidation state, so we need 3 oxygens to balance that out because each oxygen is -2 and 3 x -2 is -6

therefore Sodium Nitrate V = NaNO3

also, idk why you said NO3 is -1 (which it is because you've got the +5 of N and the -6 of O3) but then again added onto it the (wrong) oxidation state of Nitrogen.

you were nearly right, NO3 is -1 and Na is +1, so overall it's NaNO3 because +1+-1=0
Reply 11
Original post by hamzakalinle
okay so the Roman Numeral V means 5, have a look at Roman Numerals because they're commonly used in A Level Chem, and it refers to the Nitrogen.

Why? - because we already know Na is +1 always and that Oxygen is +2 always (unless it's in a peroxide, which in this case, it isn't) so it can only be referring to Nitrogen.

So; Na= +1 like you said
N= +5 because of the Roman Numeral
overall we have a plus 6 oxidation state, so we need 3 oxygens to balance that out because each oxygen is -2 and 3 x -2 is -6

therefore Sodium Nitrate V = NaNO3

also, idk why you said NO3 is -1 (which it is because you've got the +5 of N and the -6 of O3) but then again added onto it the (wrong) oxidation state of Nitrogen.

you were nearly right, NO3 is -1 and Na is +1, so overall it's NaNO3 because +1+-1=0


I got it! Thanks alot!!

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