MCQ
Among $10^{-9} g$ (each) of the following elements, which one will have the highest number of atoms?
Element : Pb, Po, Pr and Pt
Element : Pb, Po, Pr and Pt
- APo
- ✓Pr
- CPb
- DPt
✓
Answer
Correct option: B.
Pr
(B) $pr$
$
\text { No. of atoms }=\frac{\text { Massing }}{\operatorname{Molar} \operatorname{Mas}(g / mol)} \times N_{A}
$
Therefore for the same Mass element having the least Molar mass will have the higher no. of atoms.
- $M _{ P _{ o }}=209$
- $M _{ pr }=141$
- $M _{ Pb }=207$
- $M _{ Pt }=195$
$
\text { No. of atoms }=\frac{\text { Massing }}{\operatorname{Molar} \operatorname{Mas}(g / mol)} \times N_{A}
$
Therefore for the same Mass element having the least Molar mass will have the higher no. of atoms.
- $M _{ P _{ o }}=209$
- $M _{ pr }=141$
- $M _{ Pb }=207$
- $M _{ Pt }=195$
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