Question

the mass of half mole of electron is about ​

Answer 1

Plz mention the total mass also in the Ques then only I will be able to Ans...

Answer 2

Answer:

1 mole of electron contains 6.022 × 10²³ electrons.

So, 1/2 mole of electron will contain 3.011 × 10²³ electrons.

Mass of one electron is = 9.109 × 10^-28 g

So, mass of 3.011 × 10-²³ electrons will be 

\begin{lgathered}= 3.011 \times {10}^{ 23} \times 9.101 \times {10}^{ - 28} \: g \\ \\ = 27.4 \times {10}^{ - 5} \: g \\ \\ = 27.4 \times {10}^{ - 5} \times {10}^{3} \: mg \\ \\ = 27.4 \times {10}^{ - 2} \: mg \\ \\ = 0.274 \: mg\end{lgathered}=3.011×1023×9.101×10−28g=27.4×10−5g=27.4×10−5×103mg=27.4×10−2mg=0.274mg 

Therefore mass of 1/2 mole of electron is = 0.274 mg

Hope this helps...