Magnesium has 12 electrons. How many electrons will be orbiting in the outermost shell, farthest away from the nucleus? 1) 2

2) 10

3) 8

4) 4

5) 3

6) 7

Magnesium has an outer energy level of n=3 with two electrons in in its energy level. Therefor Magnesium has 2 valance electrons.

Explanation:

The correct answer is letter c 88.5%. The percent yield of H2O if 87.0 g of H2O is produced by combining 95.0 g of O2 and 11.0g of H2 is 88.5%

Here are the choices.
a 56.5% 
b 59.0% 
c 88.5% 
d 99.7%

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