A bond is non polar if it is between same atoms and polar if it is between different atoms.
Same atoms are like two dogs of same strength pulling a bone towards towards each other. But when it’s different atoms it’s like a big dog and small dog then the bone is more towards bigger dog. So it’s the same way in bonds.
Bonds are made up of electrons, when the more stronger pulling atom is present than other the electrons are more towards it and as a result we have polar bond. There is development of a kind of a negative pole and a positive pole.
The stronger atom has electrons towards itself so it has a little more negative charge while the other atom has positive charge. This makes bond polar.
So just look for bond between two different atoms, it would be polar.
Look at the pic below to see the answer.
Marked with green is bond between same atoms... one carbon and another carbon so it is not polar and test marked with blue are polar.
Well the answer should have been 10 but since the bonds at 3 and 8 are two of same type we count only one of them.
The answer is 8... well the answer should be 10 otherwise... discuss it with ur teacher
Answer:
0.001968 M min-1
Explanation:
NH2NO2(aq) --> N2O(g) + H2O(l)
[NH2NO2],M 0.978 0.476 0.232 0.113
time, min 0 255 510 765
The average rate of disappearance over the time period form t = 0 min to t = 255 min is given as;
Average rate = Change in concentration / time taken
Change in concentration = Final Concentration - Initial concentration
Change = 0.476 - 0.978 = 0.502
time taken = 255min - 0min = 255 min
Average rate = 0.502 / 255 = 0.001968 M min-1
The thing you MUST do FIRST is look for any H's, O's, or F's in the equation
1)any element just by itself not in a compound, their oxidation number is 0
ex: H2's oxidation number is 0
ex: Ag: oxidation number is 0 if its just something like Ag + BLA = LALA
2) the oxidation number of H is always +1, unless its just by itself (see #1)
3) the oxidation number of O is always -2, unless its just by itself (see #1)
4) the oxidation number of F is always -1, unless its just by itself (see#1)
ok so after you have written those oxidation numbers in rules 1-4 over each H, F, or O atom in the compound, you can look at the elements that we havent talked about yet
for example::::
N2O4
the oxidation number of O is -2.
since there are 4 O's, the charge is -8. now remember that N2O4 has to be neutral so the N2 must have a charge of +8
+8 divided by 2 = +4
N has an oxidation number of +4.
more rules:
5) the sum of oxidation numbers in a compound add up to 0 (when multiplied by the subscripts!!!) (see above example)
6) the sum of oxidation numbers in a polyatomic ion is the charge (for example, PO4 has a charge of (-3) so
oxidation # of O = -2. (there are 4 O's = -8 charge on that side ) P must have an oxidation number of 5. (-8+5= -3), and -3 is the total charge of the polyatomic ion
Answer:
Photoelectric effect, pair production and Compton scattering
Explanation:
Gamma rays, having no charge, can be slowed slowly by ionization as a material passes through. They suffer other mechanisms that eventually make them disappear, transferring their energy, they can cross several centimeters of a solid, or hundreds of meters of air, without undergoing any process or affecting the material they cross. Then they suffer one of the three effects and deposit much of their energy there. The three mechanisms of interaction with matter are: the photoelectric effect, the Compton effect and the production of pairs.
The photoelectric effect is that the photon meets an electron in the material and transfers all its energy, disappearing the original photon. The secondary electron acquires all the energy of the photon in the form of kinetic energy, and is sufficient to separate it from its atom and convert it into a projectile. This is stopped by ionization and excitation of the material
In the Compton effect the photon collides with an electron as if it were a clash between two elastic spheres. The secondary electron acquires only part of the energy of the photon and the rest takes it with another photon of lesser energy and diverted.
When an energy photon approaches the intense electric field of a nucleus, the production of pairs can happen. In this case the photon is transformed into an electron positron pair. Since the sum of the mass of the pair is 1.02 MeV, it cannot happen if the photon's energy is less than this amount. If the energy of the original photon is greater than 1.02 MeV, the surplus is distributed by the electron and the positron as kinetic energy, and the material can be ionized. The positron at the end of its path forms a positronium and then annihilates producing two annihilation photons, 0.51 MeV each.
The correct statement is " A single bond, because they overlap orbitals to share one pair of electrons." A fluorine atom is unstable with 7 electrons in its valence shell and so needs one more electron to achieve stability. This is according to the octet rule which states that an atom will gain or lose electrons until there are 8 electrons in its valence shell. So each fluorine donates an electron to form a single pair and the achieves a noble gas configuration.