The difference in the mass of 100 moles each of sodium atoms and sodium ions is 5.48002 g. Compute the mass of an electron.
ScienceClass 9CBSEAnswered 27 Mar 2026
Answer
Soln:
Sodium atom and ion differ by one electron. For 100 moles each of sodium atoms and ions there would be a difference of 100 moles of electrons.
Mass of 100 moles of electrons= 5.48002 g Mass of 1 mole of electron = 5.48002 / 100 g
Mass of one electron = 5.48002 /100 × 6.022 ×1023
= 9.1 ×1028 g
= 9.1×10-31 kg
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