JAMB - Chemistry (2021 - No. 20)
The mass of one Avogadro number of helium atoms is?
1.00gram
4.00gram
8.00gram
6.00gram
Giải thích
Avogadro's number is an absolute number: there are 6.022×10\(^23\) elementary entities in 1 mole.
helium has a molar mass of 4.0 grams per mole. So one mole of helium has a mass of 4.0 grams.