Even though Keq is supposed to be constant (no matter what the initial concentration is) our values varied from 193 to 407. This was not exactly convincing for me as the values were not as constant as I expected.
However, although our results varied between ICE charts, our average Keq (280.4, all Keq values added together and divided by 5) value matched very closely with the reported value.
Actual Value = 280
Experimental Value = 280.4
The % difference was calculated to be 0.14%