A Levels Chemistry

A dimer, X, is stable when solid but a dynamic equilibrium is set up in solution.
X(aq) = 2Y(aq)
A solution of X has an initial concentration of 0.50 mol dm3. When equilibrium has been reached
[X(aq)] has fallen to 0.25 moldm-3.
The changes in [X(aq)] and [Y(aq)] are plotted against time until equilibrium is reached. The value
of K, is then calculated.
Which graph and value for K, are correct?
graph
KImoldm3
0.54
0.4-
concentration 0.3-
A
Imol dm-3
1
0.2-
0.1-
0-
time
0.5-
0.4-
0.3-
2
concentration
B
/ mol dm-3
0.2-
0.1-
0-
time
0.5-
0.4-
1
concentration 0.3-
/ mol dm-3
C
0.2-
0.1-
0+
time
0.5-
2
0.4-
concentration 0.3-
/ mol dm-3
D
0.2-
0.1-
0-
time
>


An Introduction to Organic Chemistry | 2010 - O/N - 9701/12 | Q11