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Balancing equations

I was wondering if there are different answers to balanced equations.
ie
K + O2 = K2O

my answer:
2K + 1/2O2 = K2O
mark scheme:
K + 1/4O = 1/2K2O
online balancer:
4 K + O2 = 2 K2O

are they all correct?
(edited 5 years ago)
Only online balancer is correct

your answer should be: 2K + 1/2O2 -> K2O
mark scheme should be: K + 1/4O2 -> 1/2K2O
whats wrong with mine ?
Original post by BobbJo
Only online balancer is correct

your answer should be: 2K + 1/2O2 -> K2O
mark scheme should be: K + 1/4O2 -> 1/2K2O
Original post by Btec_Einstein
whats wrong with mine ?

Read the whole post

Only online balancer is correct

your answer should be: 2K + 1/2O2 -> K2O
mark scheme should be: K + 1/4O2 -> 1/2K2O
(edited 5 years ago)
Both answers are correct because the whole point of balancing them is to get them into the right ratio and the first and second answer are proportional to each other so they are both correct
But the best form to put it in is the big number is a whole number
All are technically correct (however you are missing O2 on the first two)
However for an answer you'd probably go with the online balancer's result.
Did the question just ask to balance the equation? Or what was it exactly?
(edited 5 years ago)
Original post by boom2003b
Both answers are correct because the whole point of balancing them is to get them into the right ratio and the first and second answer are proportional to each other so they are both correct


First and second are wrong. Oxygen molecule is O2, not O.
Original post by AzureCeleste
All are technically correct (however you are missing O2 on the first two)
However for an answer you'd probably go with the online balancer's result.
Did the question just ask to balance the equation? Or what was it exactly?


balance the combustion of K
i didnt add the 2 while posting my bad
Original post by BobbJo
First and second are wrong. Oxygen molecule is O2, not O.
Original post by Btec_Einstein
i didnt add the 2 while posting my bad

Then all are correct
Original post by Btec_Einstein
balance the combustion of K


Then as you are balancing for K, the answer would be the mark scheme. K stays as 1 mole and you make the other ones fit around it
Original post by Btec_Einstein
i didnt add the 2 while posting my bad

Can you post the full question and marking scheme?
Does it link the balancing to an enthalpy change?

If it wants the equation for the enthalpy change of formation of K2O then 2K + 1/2O2 = K2O is correct as the definition is the formation of 1 mole.
If it wants the equation for the enthalpy of combustion of K then K + 1/4O2 = 1/2K2O is correct as the definition is the combustion of 1 mole. (but asking for the enthalpy of combustion of K is a bit weird)

If it is just general balancing then
2K + 1/2O2 = K2O is best
4 K + O2 = 2 K2O is acceptable
(edited 5 years ago)

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