6. Heat of combustion is the heat released by the complete combustion of one mole of a substance.- T?
7. Catalysts are not consumed during a reaction.- F
8. In nature, processes tend to occur that lead to a higher energy state.- F
9. Concentration does not have an effect on a reaction.- F
17. Nuclear binding energy is released when a nucleus is formed.- T
18. Nuclei with an even number of protons and neutrons tend to be unstable or radioactive.- F
Chemistry - bobpursley, Thursday, October 28, 2010 at 10:53pm
You have a lousy text set of questions. Just plain awful.
7. Generally, true.
17. I have no idea what that means. When mass is formed, it came from energy. Nuclear binding energy is stored energy in the form of mass. When some of that mass is lost, energy is given off. Mass is Energy, and Energy is mass. My guess, and it is a guess, is that the question is trying to ask the opposite of "nuclear binding is released when a nucleus is broken up", which is True, so the opposite would be False. But honestly, It is one of the sorriest questions I have seen in awhile.
18. Exactly even, or about even? if it is about even, then true, except when atomic number is large, then it takes more and more nuetrons. But if it is "exactly even", then take a look at this.
(Broken Link Removed)
In rare instances, is the average atomic weight exactly double the atomic number (or neutrons= protons). Yet these elements have been around billions of years, for the most part, so are they stable? Yes, relatively so.