Respuesta :
Answer
0.03 moles
Explanation:
Given:
The molar mass of the unknown = 161.49 g/mol
Mass of the unknown = 4,475.01 milligrams
Step 1: Convert the mass given from milligram to gram.
Note: 1 milligram = 1 x 10⁻³ gram
So 4,475.01 milligrams will be
[tex]\frac{4475.01\text{ milligrams }\times1\times10^{-3}\text{ grams}}{1\text{ milligram}}=4.47501\text{ grams}[/tex]Step 2: Calculate the number of moles of the unknown.
The mole of the unknown element can be calculated by the given formula below:
[tex]\text{Mole }=\frac{Mass}{Molar\text{ mass}}[/tex]Substitute the values of mass and molar mass into the formula above:
[tex]\begin{gathered} \text{Mole }=\frac{4.47501\text{ g}}{161.49\text{ g/mol}}=0.027710756\text{ mol} \\ \text{Mole }\approx0.03\text{ mol} \end{gathered}[/tex]Therefore, there are 0.03 moles in 4,475.01 milligrams of an unknown element with a molar mass of 161.49 g/mol4
