Answer: There are 0.499 moles present in 
molecules of Boron trichloride.
Explanation:
According to mole concept, there are 
molecules present in 1 mole of a substance.
Hence, number of moles present in molecules are as follows.
Thus, we can conclude that there are 0.499 moles present in molecules of Boron trichloride.
Answer:
The limiting reactant in a reaction is the first reactant to be completely converted to products.
Explanation:
When we perform a reaction, it is not easy to measure the exact amount of the two reagents to make sure that both of them react completely. That's why typically we have a limiting reagent and a reagent in excess.
The limiting reagent is the one which determines the maximum amount of product formed, as when it's used up, the reaction stops and cannot proceed further, since the other reagent doesn't have anything to react with.
Simply speaking, the limiting reactant in a reaction is the first reactant to be completely converted to products.
The limiting reagent provides the information about the amount of the product formed, as opposed to the reagent in excess which doesn't provide any valuable information.
Answer:
The number of neutrons is obtain through the difference of the mass number and the number of electrons
Explanation:
By looking at the periodic table, you will see that Fluorine has 9 protons.
Since the number of electrons equal the number of protons, Fluorine has 9 electrons as well.
Meanwhile, it's mass number of 19, minus 10 neutrons, gives you 9 protons or electrons. Hence, the atom would be Fluorine.
As for the atomic number, it is obtainable through the periodic table itself.
