Answer:
it may also become impure,I think.
Answer:- 335 kcal of heat energy is produced.
Solution:- The balanced equation for the combustion of glucose in presence of oxygen to give carbon dioxide and water is:

From given info, 2803 kJ of heat is released bu the combustion of 1 mol of glucose. We need to calculate the energy produced when 3.00 moles of oxygen react with excess of glucose.
We could solve this using dimensional analysis as:

= 1401.5 kJ
Now, let's convert kJ to kcal.
We know that, 1kcal = 4.184kJ
So, 
= 335 kcal
Hence, 335 kcal of heat energy is produced by the use of 3.00 moles of oxygen gas.
Seems right, but if it’s just asking for one i would pick B
Neon is usually found in the form of a gas with molecules consisting of a single Neon atom. Neon is a rare gas that is found in the Earth's<span> atmosphere at 1 part in 65,000. I'm not 100% sure but i am pretty sure it is found in both places but more is in South America. Just incase, wait for someone else to answer.</span>
They bond because they want to make their outer electron shells more stable
Hope this helps
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