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how to balance (1 Viewer)

mat

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plz someone help me balance equations full stressed b4 the exam can sme one give me an example and tell me how to do the equations thanks
 

jm1234567890

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balancing equations is a natural talent... like 4unit maths

only practice will make perfect.

the is no real "method" to do it
 

mercury

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That is not true. Practise is important, but there are introductory methods.

Balancing equations, you need to take note of two important things:

1. Whether the number of atoms of a particular element are equal on both sides (mass balance)
2. Whether the charge on both sides of the equation are equal.
(charge balance)

I am not sure what sort of balancing tips you want, but for simple ones, like the Haber Process,

H2 + N2 <=> NH3

you need to balance that

in this case, u don't need to consider charge since everything's netural. you have to consider the number of atoms.
now you think to yourself how would i balance number of H atoms on both sides? the lowest common multiple is 6 for both sides.

So LHS = 3H2 + N2 RHS = 2NH3

3H2 + N2 <=> 2NH3

in this exam, N atom numbers are balanced. However in many cases they might not be. That was just a rather simple example of how to balance simple equations.

As for charge balance, I don't think they'd ask you for really hard ones, it comes handy when you are doing oxidation reduction balancing.

Do you have any specific examples u want to do?
 
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jm1234567890

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"now you think to yourself how would i balance number of H atoms on both sides? the lowest common multiple is 6 for both sides."


That is exactly my point!

How did you "know" to consider the H first?

hmmm.... you could also have considered the N in this example

However, in more complex examples if you consider the wrong atom first it wont balance.
 

mercury

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Originally posted by jm1234567890
How did you "know" to consider the H first?
However, in more complex examples if you consider the wrong atom first it wont balance.
No one is a born genius who naturally knows how to balance. It's good to give ppl tips, albeit how trivial it may seem, it might help.

And your second point is right, that's why it depends on what sort of equations you talking about.
 

Frigid

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go with ur gut instinct...

although you could try some maths and try to balance everything by comparing the coefficients of LHS and RHS.
 

eeyore

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start with the element that only occurs once
then you just keep doubling the numbers etc till you get something which works
 

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