For #3 the answer is B, for #4 the answer is F, and for #5 the answer is B.
Answer:
recording the wavelength of light
Explanation:
When an appropriate measure of energy say in the form of light of a certain wavelength, is supplied, electrons have a tendency to absorb the energy and get excited to a higher energy level. Conversely, if an electron is already at a higher energy state it will emit energy in the form of light (or heat) and return to a more stable lower energy state.
Answer:
- <u><em>0.80 mol Al</em></u>
Explanation:
<u>1) Word reaction:</u>
- Aluminum + ferrous oxide → aluminum oxide + iron
This is a single replacement reaction, in which aluminum, a more acitve metal than iron, replaces the iron in the ferrous oxide to form aluminum oxide and iron.
<u>2) Skeleton chemical equation:</u>
<u>3) Balanced chemical equation:</u>
Add the coeffcients to comply with the law of conservation of mass:
<u>4) Mole ratio of Al and FeO:</u>
<u>5) Set a proportion with the unkown and solve:</u>
- x / 1.2 mol FeO = 2 mol Al / 3 mol FeO
- x = 1.2 mol FeO × 2 mol Al / 3 mol FeO =<u> </u><u>0.80 mol Al ← answer</u>
