Posted by sandra on Tuesday, February 15, 2011 at 4:39pm.
Kp for the following reaction is 0.16 at 25°C.
2 NOBr(g) 2 NO(g) + Br2(g)
The enthalpy change for the reaction at standard conditions is +16.3 kJ. Predict the effect of the following changes on the position of the equilibrium; that is, state which way the equilibrium will shift (left, right, or no change) when each of the following changes is made.
(a) removing some NOBr(g)
(b) adding more NOBr(g)
(c) decreasing the container volume
(d) decreasing the temperature
ap chemisrty - DrBob222, Tuesday, February 15, 2011 at 5:40pm
Here is what you need to know.
This is a Le Chatelier's Principle problem. Le Chatelier's principle is an elegant one with many elegant words to describe. Students sometimes get lost in the elegant words. Here it is in simple words. Whatever we do to a system in equilibrium, the reaction will shift to UNDO what we did. Simple!.
A. removing NOBr means the reaction will shift to add more NOBr. [Remember: there are only three things to consider. a. the reaction shifts to the right, b. the reaction shifts to the left, c. there is no change.
So let's look at removing NOBr. If it goes to the right, we use up NOBr which makes it smaller. Wrong answer. The reaction shifts to the left. That forms NOBr making it greater. Does that undo what we did. Yes. So that must be the answer.
b. Adding more NOBr. The reaction will shift so as to UNDO what we did meaning it will shift to make NOBr smaller. Which way uses NOBr. That is the shift to the right (see reasoning form part a).
Now you're on your own for c and d but here are some hints.
c. Decreasing volume means increasing pressure. Shift is to side with smaller number of moles.
d. When T is involved, rewrite the equation this way using the information in the problem.
2NO2 + heat ==> 2NO + Br2
ap chemisrty - Anonymous, Thursday, December 11, 2014 at 6:55pm
Answer This Question
More Related Questions
- Check my answers? (Chemistry) - I only get one chance for each of these ...
- Chemistry - Given the elementary reaction: 2 NOBr==>2 NO + Br2 k = 0.80 Which...
- Chemistry - . For the gas reaction at low pressure 2NOBr ¡ê 2NO + Br2 ¥ÄH = +61....
- chemistry - . For the gas reaction at low pressure 2NOBr ↔ 2NO + Br2 Δ...
- Science help - Will someone please check my work for me? Molecules involved in a...
- Chemistry - Kp for the following reaction is 0.16 at 25°C. 2 NOBr(g) (reverse ...
- chemistry - For the following reaction at equilibrium, which change would shift...
- chemistry - In a reaction involving the bromination of acetone, the following ...
- chemistry - A possible mechanism for the overall reaction Br2 (g) + 2NO (g) ->...
- Chemistry - Nitrosyl bromide, NOBr, readily dissociated according to the ...