Check out some similar questions!

brokencow7 · May 31, 2012, 05:38 PM

The electron affinity of nitrogen is a +7 while those for carbon and oxygen are -122 and -141 kJ/mol, respectively. Why is it even reasonable to suggest nitrogen having a positive electron affinity with carbon and oxygen having negative electron affinities? Please fully explain.

brokencow7 · May 31, 2012, 05:40 PM

If you place aluminum triflouride into a solution of HF, which is a weak acid, you find that the pH decreases significantly (i.e. the concentration of hydrogen ion increases) as compared to the same concentration of HF alone. Explain this observation. Remember HF is a relatively weak acid.

brokencow7 · May 31, 2012, 05:45 PM

You take a 30.00 g ice cube (temperature -20 degrees C) and place it in 245.00 g of water at 22 degrees C. What will the temperature of the water be when the ice cube has just melted? Assume the specific heat capacity for ice and water is 4.184 J/K*g. If you then heat the water from this temperature to 80 degrees Celsius by burning methane (Delta H rxn= -890.31 kJ/mol), how many grams of methane would you have to use?

squiggs · May 31, 2012, 05:47 PM

The electron affinity, or EA, of nitrogen is +7 because of is electron configuration, which is [He] 2s2 2p3. Nitrogen, as a neutral atom has a half-filled p-orbital, and by Hund's Rule, that means that each p-orbital has 1 unpaired electron. In the same way that a completely filled orbital is especially stable (like the noble gases), a half-filled orbital is also extra stable. So adding 1 electron to nitrogen destabilizes it because it loses this half-filled shell when you add an extra electron.

brokencow7 · May 31, 2012, 05:52 PM

You are on the Starship Enterperise and the person in charge of preparing the weapons that are being used in a battle with the Klingons. You have found that your current photon torpedoes are not inflicting any damage on their space ship (i.e. there is no disruption of the ship's exterior structure). A photon torpedo has a mole of photons in it, all at the same energy. Your immediate superior suggests that all that has to be done is to put more photons into each torpedo. By doing this, the Klingon starship will be caused to explode, he states. Is your superior correct? If he is, why is he correct? If he is not correct, what would you do and how would you convince Captain Kirk that you are correct? You have to assume that such weapon exists.

ScottGem · May 31, 2012, 05:53 PM

Thank you for asking our help with your homework assignment. However, there are some rules we have for doing so.
Do not simply retype or paste a question from your book or study material

We won't do your homework questions for you. You were given the assignment for you to learn.

If you come up with your own answer or process and post it for us to critique that is acceptable. If you have some SPECIFIC questions that you couldn't find or didn't understand, we may help with that.
But this is your assignment, so show us you have at least attempted to complete it on your own.

Thank you.