Answer: This image is the answer to this question.
Explanation:
Answer:
B) Their valence shell is full
Explanation:
In order to be classified as a noble gas, an element must have a complete octet/ a full shell of valence electrons, as shown in answer B.
A and C are just incorrect. Since noble gasses are very unstable, D is a true statement, but is isn't the correct answer as this does not explain why they are inert.
<h3>Hope this was helpful!</h3>
<u>Answer:</u> The molecules of oxygen gas that will be reduced to water are 42 molecules
<u>Explanation:</u>
We are given:

The substance having highest positive
potential will always get reduced and will undergo reduction reaction. Here, oxygen will undergo reduction reaction will get reduced.
will undergo oxidation reaction and will get oxidized.
Substance getting oxidized always act as anode and the one getting reduced always act as cathode.
The half reactions follows:
<u>Oxidation half reaction:</u>
( × 4)
<u>Reduction half reaction:</u>
( × 6)
<u>Overall reaction:</u> 
We are given:
Molecules of
= 28
By Stoichiometry of the reaction:
4 molecules of
reacts with 6 molecules of oxygen gas
So, 28 molecules of
will react with =
molecules of oxygen gas
Hence, the molecules of oxygen gas that will be reduced to water are 42 molecules