<span>They are not seen in nature because they are always combined with something to make something else.</span>
Explanation:
M+=108 is way of representing molecular formula of a compound indicating simple numbers of each type of atom in a molecule and there is no information about the structure.
Here it given the molecule is hydrocarbon with 8 carbon atom and 12 hydrogen atom. Thus the compound is C8H12.
C8H12 has one ring and two double bonds.
Answer:169.87 g/mol
Explanation: (107.87 +14.007 + (3 x 15.999))= 169.874
Between 1858 and 1920, Mars was thought by many, including some scientists, to be very similar to Earth, only drier with a thick atmosphere, similar axial tilt, orbit and seasons as well as a Martian civilization that had built great Martian canals.
From the information provided in the question, we can see that; the electron moved up to an energy level and has an energy of 21.72 x 10-19 J.
Bohr's model of the atom tells us that electrons are found in certain specific energy levels. Energy is absorbed when an electron moves from a lower to a higher energy level and energy is released when an electron moves from a higher to a lower energy level.
Given that;
ΔE = E2 - E1
E2 = final energy level
E1 = initial energy level
E2 = ?
E1 = 16.32 x 10-19 J
ΔE = 5.4 x 10-19
E2 = ΔE + E1
E2 = 5.4 x 10-19 + 16.32 x 10-19 J
E2 = 21.72 x 10-19 J
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