Help me balance equation.. :)

Iron (III) oxide reacts with nitric acid to form iron (III) nitrate and water. Write the balanced equation.

For some reason I'm having problems with this. Haven't balanced an equation in ages.

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Reply 1

EierVonSatan

okay, can you write out the unbalanced equation?

Reply 2

Draconis

Umm, how do I do subscripts on here? :s-smilie:

Reply 3

EierVonSatan

well you don't have to...but you write ₂ (without the final space)

Reply 4

mrs_matt_tuck

Fe2O3 + 6HNO3 --> 2Fe(NO3)3 + 3H20

Reply 5

Draconis

EierVonSatan

well you don't have to...but you write ₂ (without the final space)

Fe₂O₃ + HNO₃ = Fe(NO₃)₃ + H₂O

Reply 6

Draconis

mrs_matt_tuck

Fe2O3 + 6HNO3 --> 2Fe(NO3)3 + 3H20

Ah, of course. I was forgetting that the 2 in front of Fe also meant that I double (NO3)3.

Thanks! :biggrin:

Reply 7

Jimny

mrs_matt_tuck

Fe2O3 + 6HNO3 --> 2Fe(NO3)3 + 3H20

That. Formatted Fe₂O₃ + 6HNO₃ = 2Fe(NO₃)₃ + 3H₂O

Reply 8

Kyalimers

Balance the Fe's first.
Then balance the H's
Lastly the O's.

Reply 9

Draconis

Got it now, thanks everybody :biggrin:

Reply 10

Eden01

Draconis

Iron (III) oxide reacts with nitric acid to form iron (III) nitrate and water. Write the balanced equation.

For some reason I'm having problems with this. Haven't balanced an equation in ages.

Back to college already??

Reply 11

seanwarby

Write the equation:

a Fe2O3 + b HNO3 -> c H2O + d Fe(NO3)3

Then balance the elements

Fe: 2a = d
O: 3a + 3b = c + 9d
H: b = 2c
N: b = 3d

a Fe2O3 + b HNO3 -> 0.5b H2O + 0.3b Fe(NO3)3

O: 3a + 3b = 0.5b + 3b therefore b = 6a

0.17b Fe2O3 + b HNO3 -> 0.5b H2O + 0.33b Fe(NO3)3

Removing common factor b

0.17 Fe2O3 + HNO3 -> 0.5 H2O + 0.33 Fe(NO3)3

Divide by lowest number

1 Fe2O3 + 6 HNO3 -> 3 H2O + 2 Fe(NO3)3

That's the way I go about it when I'm stuck anyways, helped in the Olympiad and bmat.

Reply 12

Draconis

Oh, I need to include state symbols. So, iron oxide = solid, nitric acid = aq, iron nitrate = solid, water = l, right?

Reply 13

EierVonSatan

seanwarby

That's the way I go about it when I'm stuck anyways, helped in the Olympiad and bmat.

lol never seen that method before :p:

Draconis

Oh, I need to include state symbols. So, iron oxide = solid, nitric acid = aq, iron nitrate = solid, water = l, right?

yup

Reply 14

Draconis

EierVonSatan

lol never seen that method before :p:

yup

Thanks

Reply 15

seanwarby

EierVonSatan

lol never seen that method before :p:

It's awesome! :P my chemistry teacher told me he was taught it at Oxford so it must be at least partially useful!

Reply 16

EierVonSatan

seanwarby

It's awesome! :P my chemistry teacher told me he was taught it at Oxford so it must be at least partially useful!

lol ok, it's definitely a good method to get the answer reliably, but I think its a tad over the top :p:

Reply 17

seanwarby

EierVonSatan

lol ok, it's definitely a good method to get the answer reliably, but I think its a tad over the top :p:

Well yeah... I mean, I don't use it for every single equation I need to balance, but the times that I've been struggling to work out the equation for 5 minutes It's great (at least you know If it doesn't balance with that method you've got the equation wrong).

Reply 18

Cowz

seanwarby

It's awesome! :P my chemistry teacher told me he was taught it at Oxford so it must be at least partially useful!

Why do you reference Oxford in such a way that implies it matters he was taught that method at Oxford?

All you did was produce a method for solving two simultaneous equations. Same as it taught in every GCSE maths class.

Reply 19

Draconis

One more question: I have to write the ionic formula of CaCl₂, is it Ca²⁺Cl₂⁺?
For some reason I have a feeling that you can't have subscripts in ionic formulae.. I don't know why I think that. :s-smilie: