The gases hydrogen, oxygen, carbon dioxide, sulphur dioxide and chlorine are arranged in order of their increasing relative molecular mass. Given 10 g of each gas at STP, which gas will contain the least number of molecules and which gas the most?

Explanation

To solve the problem, we need to determine the number of molecules present in 10 g of each gas at STP (Standard Temperature and Pressure). The number of molecules can be calculated using the formula:

\[ \text{Number of molecules} = \left(\frac{\text{mass of gas (g)}}{\text{molar mass (g/mol)}}\right) \times N_A \]

where \(N_A\) is Avogadro's number, approximately \(6.022 \times 10^{23}\) molecules/mol.

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