Question
Download Solution PDFWhich one of the following has different number of molecules? (All kept at normal temperature and pressure)
Answer (Detailed Solution Below)
Detailed Solution
Download Solution PDFThe correct answer is option 4 i.e. 2 grams of carbon.
Number of moles
- The number of moles can be calculated by Mass (g) divided by Molecular mass.
- \(Number\space of\space moles = {Mass(g) \over Molecular\space mass\space (M)}\)
- We know the same number of moles have the same number of molecules or atoms.
- 3 grams of Hydrogen = 1.5 moles, because the molecular mass of Hydrogen is 2.
- 48 grams of Oxygen= 1.5 moles, because the molecular mass of Oxygen is 32.
- 42 grams of Nitrogen = 1.5 moles, because the molecular mass of Nitrogen is 28.
- 2 grams of carbon = 0.167 moles, because the molecular mass of carbon is 14.
- Hence option 4 is correct.
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