 # In an equilibrium A+B=C+D A & B are mized in a vessle at tempT. the initial conxntration of A was twice the initial concntration of B. After equillibrium has established ,concentrationof c was thrice the equilibrium concentration of B . calculate Kc??

9 years ago

dear priyanka dubey

according to the given information the equationbecomes as

2A+B=3C+D

FROM THIS Kc EQUALS TO [D][C]^3 DIVIDED BY [B][A]^2

9 years ago

CONSIDER THE INTIAL MOLES OF ''A'' BE ''a''  AND MOLES OF ''B'' BE ''b'' AND MOLES LOST BY ''A'' AND ''B'' BE X

A  +  B ---------------->  C  +  D

INITIAL MOLES:                                                    a         b                                       0        0

EQUILIBRIUM MOLES :                                          a-x       b-x                                   0+x       0+x

ACCORDING TO STICHIOMETERY AND SINCE THE COEFFICIENTS ARE 1 IF X MOLES ARE LOST BY ''B'' SO ''A'' WILL ALSO LOSE X MOLES

IT DOESNOT MATTER IF YOU WORK IN MOLES OR CONCENTRATION BECAUSE IT IS SAMETHING

ACCORDING TO THE INFORMATION    a=2b  AND (0+x)=3(b-x)  SO FROM THIS EQUATION YOU GET THE VALUE OF x WHICH IS (3b)/4

NOW KC= [C]1 [D]1  DIVIDE BY [A][B]1          [    ] SIGN INDICATES MOLAR CONCENTRATION

KC= x * x divide by (a-x) (b-x)

i didnt write the concentration which is moles upon volume beacuse volume term gets cancelled so now you have ''a'' in terms ''b'' and ''x'' in terms of ''b'' substitue those values in the equation and ''b'' term wil get cancelled and you will get your answer

PLZ DO APPROVE THE ANSWER IF YOU ARE SATISFIED