Answer:
0.0286 moles
Explanation:
Given mass, [tex]m=3.1\times 10^{-1}g=0.31\ g[/tex]
Molar mass of boron, M = 10.811 g/mol
[tex]\text{No of moles}=\dfrac{\text{given mass}}{\text{molar mass}}\\\\n=\dfrac{0.31}{10.811 }\\\\n=0.0286[/tex]
Hence, there are 0.0286 moles in given mass of boron.
