Answer:
[tex]\boxed{\text {4.0 mol}}[/tex]
Explanation:
1 mol of Be = 9.012 g
[tex]\text{Moles of Be} = \text{36 g Be} \times \dfrac{\text{1 mol Be}}{\text{9.012 g Be}} = \text{4.0 mol Be}\\\\\text{There are }\boxed{\textbf{4.0 mol Be}} \text{ in 36 g of Be}[/tex]
Answer: Option (b) is the correct answer.
Explanation:
It is known that number of moles of a substance is equal to the given mass of the substance divided by its molar mass.
Mathematically, Number of moles = [tex]\frac{mass}{/text{\molar mass}}[/tex]
Molar mass of beryllium is 9 g/mol. Hence, putting the given values into the above formula as follows.
Number of moles = [tex]\frac{mass}{/text{\molar mass}}[/tex]
= [tex]\frac{36}{9 g/mol}[/tex]
= 4 moles
Thus, we can conclude that the number of moles present in 36 grams of Be are 4 moles.
