Beryllium has 4 protons, 4 electrons and 5 neutrons
Answer:
Cobalt/Electron configuration
Explanation:
[Ar] 3d7 4s2
Answer:- A) 1 mole of Fe and 1.5 moles of
.
Solution:- The balanced equation is:

From balanced equation, there is 1:3 mol ratio between
and CO, From given data, 3 moles of
and 1.5 moles of CO are taken for the reaction. CO is the limiting reactant as it's moles are less than the other reactant and which is also clear from the mole ratio. We could do the calculations also to support this. Let's calculate the moles of CO required to react completely with given 3 moles of
.

= 9 mol CO
So, from calculations, 9 moles of CO are required to react completely with 3 moles of Iron(III)oxide but only 1.5 moles of CO are available. Hence, CO is the limiting reactant and the product moles are calculated from this as:

= 1 mol Fe

= 1.5 mol 
So, the correct choice is A) 1 mole of Fe and 1.5 moles of
.