Ok heres what i know, one of the reasons why visible light will pass through glass but not through other materials is because the molecules in glass require more energy than average to push electrons from one level to another. Photons in visible light simply do not have enough energy. Only photons of light with shorter wavelengths, such as those that make up ultraviolet light, have the ability to change the electrons in glass. This is why ultraviolet light is unable to pass through glass. Lol im in 6th grade this is all i know ! :)
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<h3>Further explanation
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Electrons can move the shell up or down by releasing energy or absorbing energy
Excited electrons show higher electron transfer to the shell by absorbing energy
So it can be concluded that there are 2 conditions:
Ground state is the state of electrons filling shell with the lowest energy levels.
Excited state is the state of electrons which occupies a higher energy level
The state of excited electrons can be seen from the presence of electrons which do not fill the skin completely but fill the skin afterward
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From its 8 electron configuration, filling 3 shells, 2 electrons in the firs shell, 7 electrons in the second shell and 1 electron in the third shell
the electrons in the third shell should fill the electrons in the second shell first according to Aufbau rule (lower energy shells)

Answer:
2nd option is NOT a postulate of kinetic theory of gases
Explanation:
actually particles move in straight random motion and create bombardment with the molecules and container
Answer:
C. Lithium
Explanation:
I Goo gled it and I think that's right.
The much of the sample that would remain unchanged after 140 seconds is 2.813 g
Explanation
Half life is time taken for the quantity to reduce to half its original value.
if the half life for Scandium is 35 sec, then the number of half life in 140 seconds
=140 sec/ 35 s = 4 half life
Therefore 45 g after first half life = 45 x1/2 =22.5 g
22.5 g after second half life = 22.5 x 1/2 =11.25 g
11.25 g after third half life = 11.25 x 1/2 = 5.625 g
5.625 after fourth half life = 5.625 x 1/2 = 2.813
therefore 2.813 g of Scandium 47 remains unchanged.