Answer:
Energy is released.
Explanation:
When an electron absorbs energy, it moves up into an excited state. When it releases energy, it will return to the ground state.
<u>Answer:</u> The correct answer is Option A.
<u>Explanation:</u>
Mole ratio is defined as the ratio between the stoichiometric coefficients of the molecules present in the chemical reaction.
For the given balanced chemical equation:

By Stoichiometry of the reaction:
3 moles of iron metal reacts with 4 moles of water to produce 1 mole of iron oxide and 4 moles of hydrogen gas.
The mole ratio of 
Hence, the correct answer is Option A.
It would be a,b,c as the answer. hope this helps!
Answer: M-18
Explanation:
The mass spectra of alcohols often fail to exhibit detectable M peaks but instead show relatively large __M-18___ peaks.
Mass spectroscopy is used to determine the molecular mass and molecular formula of a sample.
When the mass spectra of alcohols do not show detectable M peaks, they show relatively large M-18 peaks.
yes, because they are combined in different ratios.