Answer: Which elements are found in the greatest number of substances?
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Chemical Name Sucrose
Chemical Formula C12H22O11
Number of Elements 3
Name of Elements Carbon, Hydrogen, Oxygen
Number of Atoms 45
Explanation:
Answer: -
The experiment Niven is doing is burning of Mg.
The first step would be finding the molar mass of MgO
Atomic mass of Mg = 24 g
Atomic mass of Oxygen = 16 g
Molar mass of MgO = 24 x 1 + 16 x 1 = 40 g
The balanced chemical equation for this reaction is
2 Mg + O2 -- > 2MgO
From the balanced equation we see that
2 Mg gives 2 MgO
2 x24 g of Mg O gives 2 x 40 g of MgO.
28g of MgO gives

= 46.66 g of MgO.
The answer is: Electrons are shared in each pi bond. If the pi bonds flip back and forth between the adjacent p-orbitals on the two sides of an atom, the shared electrons in the p-orbitals can become delocalized.
Hope this help