Question

number of moles after equilibrium has reached
please explain this to me, i have no clue what to think of

Answer 1

@emcrazy14 @Kainui

Answer 2

i don't know what to do, im not even given volume to find concentration or at least there is no mention of at room temperature and pressure or at standard temperature and pressure T_T

Answer 3

You have to do this by the equilibrium (Kc) method.

Answer 4

@somy: My bad.
That's actually Kc= x^2/(1-x)^2

Answer 5

\[4=\frac{ x ^{2} }{ (1-x)^{2} }\]

Answer 6

@Somy they didn't give you volume, but it's actually not important and I'll show you why!

Since equilibrium constants are concentrations, and concentration is recorded as mol/L then let's just plug in concentrations as capital letters with brackets and the number of mols as the lower case letter with V as the volume.

\[K_c=\frac{[C][D]}{[A][B]}=\frac{ \frac{c}{V} \frac{d}{V}}{ \frac{a}{V} \frac{b}{V}}=\frac{cd}{ab}\]

So you can use mols just as fine as concentrations, it all works out. =)

Answer 7

ohhhhh okaaay let me try now @Kainui

Answer 8

Taking square root on both sides;
\[\sqrt{4}= \sqrt{\frac{ x ^{2} }{ (1-x)^{2} }}\]
\[2= \frac{ x }{ (1-x) }\]
\[2-2x=x\]
\[3x=2\]
\[x=\frac{ 2 }{ 3 }\]

Answer 9

@emcrazy14 showed the correct technique of how to do it, I just wanted to give you a little extra info

Answer 10

@emcrazy14 i'll try it myself then look at ur working ok?

Answer 11

@somy: I'm sorry. Sure. I did that for @KL-RC . :)

Answer 12

i do know that way of working, i was just confused about volume not being there :)

Answer 13

ah no need to apologize lol i said that because me doing on my own might take time, and so i might have questions to ask :D so don't leave lmao @emcrazy14

Answer 14

Okay. :D

Answer 15

yuppp i got it right :D thank u guys!!! :* @Kainui @emcrazy14

Answer 16

Well done. *_*

Answer 17

how's physics? @emcrazy14

Answer 18

Really bad. I get so many wrong. >_<

Answer 19

im freaking out right now, tomorrow we are going to start with physics @emcrazy14

Answer 20

which year r u doing? @emcrazy14

Answer 21

Before 2005.

Answer 22

O_O isn't that too far? @emcrazy14

Answer 23

They rarely repeat the questions. So practising whatever year won't make a difference I guess. They will always come up with something new. >_<

Answer 24

well i guess so also, but i thought latest years would be better T_T