What is the number of molecules present in 16 g of O₂ at S.T.P.?
WBBSE
Class X
Physical Science
Chemical Calculations
01 Mark
2025
3.011 × 10²³
Explanation:
Given mass = 16 g
Molecular mass = 32 g
No. of moles = 16\over 32 = 0.5
Number of molecules = 0.5 × 6.022 × 10²³ = 3.011 × 10²³.
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