Answer:
Explanation:
Electrons are the negatively charged particles of an atom that are involved in chemical reactions. They are located outside the nucleus of an atom
B, I would believe. There are 58, but B is the closest we can get.
Answer:
Explanation:
1 mol of methane = 6.02 * 10^23 molecules
6.70 mol of methane = x
Cross multiply
x = 6.70 * 6.02 * 10^23
x = 4.033 * 10^23 molecules.
Answer:
4.823 x 10^-19 J
Explanation:
Energy is calculated by E = hv where h - Planck's constant in joule.s
v - frequency.
in this particular question the wave length is 4.12 x 10^-7 m. to exhaustively use this we need a relation between wave length & frequency. c=wv where C is approximately 3 x 10^8m/s
-v = c/w = 3x10^8m/s / 4.12 x 10^-7m = 7.28 x 10^14 Hz or 1/sec
now we can simply use Planck's constant in E=hv =
(6.626 x 10^-34) x (7.28 x 10^14Hz) = 4.823 x 10^-19 J.