Ha!
Worked solutions:
1) C
It is moving to the right. The red will decrease. So A,B are wrong. D suggests linearity, something that *wont* happen in real life situations involving such equilibria. Hence C is the required answer.
2) B. Since we are dealing with different states, increasing gas pressure is the least likely to affect this. A increases surface area and hence will increase. All the rest are quite trivial.
3) B. It says *mainly* and whilst A is correct this only accounts for a small increase.
4) D. A supposes you are taking the reverse of one reaction. You aren't. its a hypothetical. B is describing an exothermic. Di is right because if you draw a small graph, the activation energy is always greater than delta H.
5) A. Difference is 60. We have multiplied the equation by 3. So times 60 *3 = 180. It has released heat, so -180.
6) D. Reverse reaction has an activation energy of 40+20+30 = 90. Times this by 2 we get 180.
7) A. simple maths.
C. Use whatever means you use. You start with 0.5 mol of NO2 and 0.2 remains. So the change is 0.3. in concentration thats 0.03. 0.03/2 is formed of N2O4. So 0.015. then use K value.
9) D. Just use number of particles. 5 -> 3 this means thatif we increase pressure it will want to decrease it, so it will go to the right. This is what we want.
10) C. Look for an endothermic and one where more particles on the right.
1 a) Yeah........ kinda confused here. The point X from what i can see refers to a specific kinetic energy.
ii) Draw a pretty graph with the *dicky* end more to the right and similar areas underneath.
iii) An increase in temp increases the average kinetic energy of the system. This means that there is a greater proporion of particles with sufficient enregy to overcome the activation complex.
bi) At the beginning of the reaction where the concentrations of both reactants are at their peak.
ii) No more H2 is produced, the reaction has gone to completion.
iii) work out what the effect of using 1g of magnesium will do. To do this look at what the 2g was doing. See what is the limiting reagent.
Mg -> 2/24.3 vs 0.15*2
0.08 vs 0.3
Ratio is 1: 2 so clearly, Mg is limiting.
If we were working with 1 gram of Mg it would also limit, but the value of the mass of H would be lower because we are using less mol of Mg and the Mol of Mg determines the mol and hence the mass of H2.
Graph should have a greater rate than the first due to it being powdered but at t1 taper off arbitrarily lower.
iv) Increase the temperature.
Use a suitable catalyst.
Increase concentration of reactants.
2) column on the left going down is : Left (endo),right,right (less particles),No change (position isn't affected by this).
opposite: Decrease, no change, no change, no change (coz only temperature effects this bad boy)
3) ai) I refuse to answer this question. if you can't do this, GTFO out of chemistry NAO!
ii) 88.1
b) refer to link:
http://img718.imageshack.us/f/chemcs.jpg/ci) +160. It is the back reaction. So the change in H is just the positive of the original enthalpy.
ii) Change in H + activation energy = 160 + 40 = 200kjmol^-1
d) refer to link -
http://img94.imageshack.us/f/chem1j.jpg/Logic for ai in 4.
You start off with intial concentrations. the reactants decrease by x amount. The product increases by same x amount.
Do.not.bag.my.handwriting. :knuppel2: :knuppel2: :knuppel2: :knuppel2: :knuppel2: :knuppel2: :knuppel2:
Not sure on: 3,4,1ai. Correct any of my mistakes :smitten:
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