You have posted five questions and I don't see any effort on your part AND you don't explain what your trouble is in knowing what to answer. So let me give you a mini lesson in LeChatelier's Principle, answer a couple of questions and leave the others to you.
First, and this is important, in order for us to use LeChatelier's Principle the SYSTEM MUST BE AT EQUILIBRIUM.
Second, I can give you a very precise and from a chemists viewpoint, and a very esoteric definition of the principle. I can tell you from personal teaching experience that most students get confused with it and make the questions hard when the chemistry isn't that hard. So let me give you a boiled down statement. Here it is. When we do something to a system AT EQUILIBRIUM (change temperature, change pressure, change concentration, etc), the system will try to undo what we did to it. Simple. So how does that apply? Here is question 3.
3. Use the reaction to answer the question
N2(g) + 3H2(g) <> 2NH3(g) + energy
When this reaction has reached equilibrium, how will it respond when the temperature of the system increases?
Notice that the reaction is exothermic (it gives off heat; i.e., energy) so adding heat will upset the equilbrium. The reaction will undo what we did to it. How can it undo adding the heat? It can shift to the left in order to make the reaction go in reverse thereby using up the heat we added. Its exothermic going to the right or endothermic going to left. So by going to the left, we use up the added heat, we produce more of the reactants (N2 and H2) and also use some of the products (NH3) in the process.
Here is #4.
4.Use the chemical reaction to answer the question.
CH4(9) + H2O(g) + energy <> 2 CO(g) + H2(9)
Which statement best describes the effect of adding more steam to the system?
I would have preferred the question to include being at equilbrium, in fact I think all of them should say something about being in equilibrium. So if we do something like adding steam the system at equilibrium will react to get rid of the extra steam. How can it do that? Easy. It shifts the reaction to right which has the effect of using up the added steam (at least some of it) which also reduces the concentration of CH4 and uses extra energy. In the process, of course, it will produce more
CO and H2. Actually, adding anything to to reactant side will shift it to the right and adding anything to the product side will shift the reaction to the left.
One final helper which is slightly different and involves pressure. Here is #5 again.
5. Use the reaction to answer the question.
CO(g) + H2O(g) <> CO2(g) + H2(g) + energy
This question isn't anywhere but it has as an answer about pressure changing and since that answer is dealt with slightly different I want to cover it here. When a system in equilibrium changes pressure, you answer it by counting the moles on each side. For an INCREASE in pressure the reaction will shift to the side with fewer moles of gas. For a DECREASE in pressure the reverse will be true. So for this reaction increase OR decrease in pressure has no effect because you have 2 moles gas on the left and 2 moles gas on the right. Look at problem 1. An increase in pressure will shift the reaction to the right (4 moles gas on the left and 2 mols on the right) but a decrease in pressure will shift the reaction to the left.
HOPE THIS HELPS.
1. Use the reaction, which produces ammonia, to answer the question.
N2(g) + 3H2(g) <> 2NH3(g)
Which change would happen in the system if the concentration of N2 was increased at constant pressure?
O The reverse reaction would increase in order to increase the pressure.
O The reverse reaction would increase to start reducing the concentration of N2.
O The forward reaction would increase to start reducing the concentration of N2.
O The forward reaction would increase in order to increase the pressure.
2. In which situation can Le Chatelier's principle be applied?
O it can be applied when a reaction happens in a single direction, and environmental conditions are kept
constant
O it can be applied when a reaction is reversible, and environmental conditions are changed.
O It can be applied when a reaction happens in a single direction, and environment conditions are changed.
O It can be applied when a reaction is reversible, and environmental conditions are kept constant.
3. Use the reaction to answer the question
N2(g) + 3H2(g) <> 2NH3(g) + energy
When this reaction has reached equilibrium, how will it respond when the temperature of the system increases?
O The equilibrium will shift to the left
O The equilibrium will shift to the right.
O The concentration of H2 will decrease.
O The concentration of N2 will decrease.
4.Use the chemical reaction to answer the question.
CH4(9) + H2O(g) + energy <> 2 CO(g) + H2(9)
Which statement best describes the effect of adding more steam to the system?
O Adding steam allows more molecules of the reactants to collide, causing the rate of the forward reaction to increase
O Adding steam allows more molecules of the products to collide, causing the rate of the reverse reaction to
increase
O Adding steam allows more molecules of the products to collide, causing the rate of the forward reaction to
increase
O Adding steam allows more molecules of the reactants to collide, causing the rate of the reverse reaction to
increase
5. Use the reaction to answer the question.
CO(g) + H2O(g) <> CO2(g) + H2(g) + energy
Which change to the system would be favorable to the forward reaction?
O an increase in pressure
O an increase in the concentration of CO
O a decrease in pressure
O an increase in the concentration of CO2
8 answers
Question 1: The forward reaction would increase to start reducing the concentration of N2.
Question 2: It can be applied when a reaction is reversible, and environmental conditions are changed.
Question 3: The equilibrium will shift to the left.
Question 4: Adding steam allows more molecules of the reactants to collide, causing the rate of the forward reaction to increase.
Question 5: an increase in the concentration of CO
Your welcome, now you don't have to read drbob's essay.
Question 2: It can be applied when a reaction is reversible, and environmental conditions are changed.
Question 3: The equilibrium will shift to the left.
Question 4: Adding steam allows more molecules of the reactants to collide, causing the rate of the forward reaction to increase.
Question 5: an increase in the concentration of CO
Your welcome, now you don't have to read drbob's essay.
"Not An Essay" was right and is a G!! thanks dude
Why is DrBob so rude??????
DrBob if we wanted to study the lesson we wouldn't have went online purposefully here to find and actual clear answer <-<
also "Not an Essay" was correct thank you
DrBob you should stick to being A doctor instead of a English / chemistry teacher
I actually found DrBob222's "essay" extremely helpful. The first line might have been a little harsh, but they explained how to answer each question without directly giving out the answer. Now I actually understand the lesson.
There are students out here who look up questions because the lesson didn't make sense. Thank you DrBob222 for giving me an answer that helped me learn.
There are students out here who look up questions because the lesson didn't make sense. Thank you DrBob222 for giving me an answer that helped me learn.
1 answer