For the first one the answer is B. and the second one is D.
There can only be two electrons in the innermost shell of an atom so b is the correct answer
A cation (+) will be smaller than its neutral atom, while anion (-) will be larger than its neutral atom.
In 1770 a Scottish physician and Chemist Daniel Rutherford performed a simple experiment with which he discovered nitrogen. Rutherford being with an empty bottle that he turned upside down in a pan of water so that the air was trapped. A buring candle was placed inside the bottle with the trapped air causing the water to rise a bit. The part of the air that seemed to "disappear" when the candle was bured was oxygen gas and the part of the air that did not "disappear" Ruthford discovered Nitrogen.
1 mol of any substance is made of 6.022 x 10²³ units, these units could be atoms making up elements or molecules making up a compound.
In this case. 1 mol of Li is made of 6.022 x 10²³ atoms of Li
The molar mass of Li is 6.94 g/mol
Therefore mass of 1 mol of Li is 6.94 g
In 6.94 g of Li there are - 6.022 x 10²³ atoms
Then in 766.3 g of Li there are - 6.022 x 10²³ atoms / 6.94 g x 766.3 g = 665 x 10²³
There are 6.65 x 10^25 atoms of Li
