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# Super quick balancing equation question watch

1. CaO + 2H2O + SO2 ----> CaSO3 + 2H2O

I know I'm probably missing something really obvious here, but why is it necessary for there to be a 2 in front of both the H2O? Surely they would just cancel each other out?
2. You're right you don't need the 2, the CaO and SO2 balance the CaSO2. Equation looks like it's already balanced
3. (Original post by leverarch)
CaO + 2H2O + SO2 ----> CaSO3 + 2H2O

I know I'm probably missing something really obvious here, but why is it necessary for there to be a 2 in front of both the H2O? Surely they would just cancel each other out?
The quantity of atomic elements must be preserved: Matter can neither be created nor destroyed.

Do not confuse with simple algebraic manipulation of the chemical formulae. Atoms do not cancel out !

CaO + 2H2O + SO2 comprises these quantities of elements:

Ca, O + (H, H, O), (H, H, O), + S, O, O

i.e.

1 x Calcium atoms

5 x Oxygen atoms

4 x Hydrogen atoms

1 x Sulphur atoms

= 11 atoms in total.

Therefore all 11 atoms appearing on the left hand side of the equation must all be present on the right hand side of the equation.
4. (Original post by uberteknik)
The quantity of atomic elements must be preserved: Matter can neither be created nor destroyed.

Do not confuse with simple algebraic manipulation of the chemical formulae. Atoms do not cancel out !

CaO + 2H2O + SO2 comprises these quantities of elements:

Ca, O + (H, H, O), (H, H, O), + S, O, O

i.e.

1 x Calcium atoms

5 x Oxygen atoms

4 x Hydrogen atoms

1 x Sulphur atoms

= 11 atoms in total.

Therefore all 11 atoms appearing on the left hand side of the equation must all be present on the right hand side of the equation.
But then even if you didn't have the 2 in front of the H2O, that would put 8 atoms on the left which would equal the 8 atoms that would then be on the right
5. (Original post by LilN)
You're right you don't need the 2, the CaO and SO2 balance the CaSO2. Equation looks like it's already balanced
According to my school notes and the internet, there needs to be a 2 in front of it but it seems balanced to me which is why I'm confused
6. (Original post by leverarch)
According to my school notes and the internet, there needs to be a 2 in front of it but it seems balanced to me which is why I'm confused
(Original post by leverarch)
But then even if you didn't have the 2 in front of the H2O, that would put 8 atoms on the left which would equal the 8 atoms that would then be on the right
Balancing the formulae must be done in the context of the chemical reaction:

Calcium Oxide CaO, reacts with water 2H2O, to produce the aqueous solution slaked lime (Calcium Hydroxide) Ca(OH)2

Calcium Hydroxide Ca(OH)2 reacts with Sulphur Dioxide SO2 to produce Calcium Sulfite CaSO3 + Water 2H2O
7. (Original post by uberteknik)
Balancing the formulae must be done in the context of the chemical reaction:

Calcium Oxide CaO, reacts with water 2H2O, to produce the aqueous solution slaked lime (Calcium Hydroxide) Ca(OH)2

Calcium Hydroxide Ca(OH)2 reacts with Sulphur Dioxide SO2 to produce Calcium Sulfite CaSO3 + Water 2H2O
Oh okay thank youuu

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