i have looked all over my text book for the answers to these questions and its driving me crazy because i cant find them. please help it would be greatly appreciated :) .
1. what property of isotopes are responsible for their value in biological research?
2. what determines the reactivity of an atom?
3.molecules that contain covalent bonds typically have regions of positive and negative charge and thus are polar. however some molecules containing polar covalent bonds are nonpolar. explain how this is possible.
please help! thanx alot! :)
2006-09-06 16:38:06 · 4 answers · asked by Simply Me 1 in Science & Mathematics ➔ Chemistry
1. Their radioactivity. In research, isotopic labeling is done to study the mechanism. Labeled carbons are always easily detected. The position of the labeled carbon reveals the mechanism in many organic reactions.
2. binding energy per nucleon determines the stability of a nuclide (atom) and thus the reactivity. Atoms having a higher binding energy are stable - atoms having lower atomic numbers. Atoms having a lower binding energy are less stable and highly reactive. I'd suggest you read "Stability Belt" section in your text.
3. Some compounds are non-polar despite having polar bonds. The polarity of one bond is neutralized by the polarity of the other bond in the opposite direction. Consider CO2 for example. CO bond is polar, but, the polarity of one CO bond is neutralized by the polarity of the other CO bond, thus causing zero polarity, ie., zero dipole moment.
2006-09-06 17:24:07 · answer #1 · answered by Logesh 2 · 0⤊ 0⤋
1. Different isotopes of an element can be differentiated, but they have identical chemical properties. So it's a way to tag atoms in a series of complex biological processes, and follow atoms of each element to see where they end up.
2. The number of electrons in the valence shell. So if you've got just 1 atom in the outer shell you've got an electropositive group 1 metal, if you're 1 atom short of a full outer shell you've got an electronegative halogen, and if you've got a full outer shell, it's an inert gas.
3. At one extreme you've got an ionic compound like sodium chloride, with a negative ion joined to a positive one. At the other extreme you've got complete charge symmetry, like methane, where all 4 hydrogen atoms joined to the central carbon are identical. But you've got umpteen intermediate cases like CHCl3, where the H is a little bit more positive than the rest of the molecule.
2006-09-07 00:57:14 · answer #2 · answered by zee_prime 6 · 0⤊ 0⤋
hi ok i may help you by giving you that
2006-09-06 23:51:56 · answer #3 · answered by it's the life 1 · 0⤊ 0⤋
this link answers the 1st question
http://www.accessexcellence.org/AE/AEC/CC/radio_table.html
2006-09-06 23:48:43 · answer #4 · answered by Anonymous · 0⤊ 0⤋