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# Kc

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1. What do i do any help welcome no idea what i'm doing. The teacher went from writing things correctly using the formula to this so i have 100& no idea what's happening but i can guess.

2. (Original post by thefatone)
What do i do any help welcome no idea what i'm doing. The teacher went from writing things correctly using the formula to this so i have 100& no idea what's happening but i can guess.

Do you know how to create the equation of Kc.
Kc=[products]^a/[reactants]^b

Where [.....] means concentration.
And where each of the reactants and products is raised to the power of the number of moles of them. So in your first example to the power 1 so can be ignored.

Also for the equilibrium moles of ethyl ethanoate and H20, Consider what must have happened for the moles of ethanoic acid and ethanol to increase.
3. (Original post by SamuelN98)
Do you know how to create the equation of Kc.
Kc=[products]^a/[reactants]^b

Where [.....] means concentration.
And where each of the reactants and products is raised to the power of the number of moles of them. So in your first example to the power 1 so can be ignored.

Also for the equilibrium moles of ethyl ethanoate and H20, Consider what must have happened for the moles of ethanoic acid and ethanol to increase.
Obviously reduce to bring it to equilibrium but reduce to what?
are the number of moles within a closed system the same?
or do they change?

without knowing the answer to whether the number of moles stays the same i can't work out the number f moles at equilibrium
4. (Original post by thefatone)
Obviously reduce to bring it to equilibrium but reduce to what?
are the number of moles within a closed system the same?
or do they change?

without knowing the answer to whether the number of moles stays the same i can't work out the number f moles at equilibrium
You can use the ratio of moles to work out the number of moles of each thing at equilibrium. Eg if I had 2A +3B <-----> C then if 2 moles of A have reacted than i have one mole of C
5. (Original post by samb1234)
You can use the ratio of moles to work out the number of moles of each thing at equilibrium. Eg if I had 2A +3B <-----> C then if 2 moles of A have reacted than i have one mole of C
so everything's just 0.300 moles then in the middle column?
6. (Original post by thefatone)
so everything's just 0.300 moles then in the middle column?
No. 0.3moles have reacted, so how much do we have left
7. (Original post by samb1234)
No. 0.3moles have reacted, so how much do we have left
0.2?
8. (Original post by thefatone)
0.2?
Sorry was working. If we started with 1 mole and 0.3mole react than we have 1-0.3=0.7 moles at equilibrium
9. (Original post by samb1234)
Sorry was working. If we started with 1 mole and 0.3mole react than we have 1-0.3=0.7 moles at equilibrium
which box does this go in?
10. (Original post by thefatone)
which box does this go in?
the equilibrium moles of ethyl ethanoate and water
11. (Original post by samb1234)
the equilibrium moles of ethyl ethanoate and water
ok so is the conc. column below it's the same? 0.7/v like they've done?
12. (Original post by thefatone)
ok so is the conc. column below it's the same? 0.7/v like they've done?
yep

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