(a) The number of molecules contained by the balloon at the given condition is 6,438.97 moles.
(b) The mass of air in the balloon is 186.73 kg.
The given parameters;
The number of molecules contained by the balloon at the given condition is calculated as follows;
[tex]PV = nRT[/tex]
where;
[tex]n = \frac{PV}{RT} \\\\n = \frac{10,100 \times 1500}{8.314 \times 283} \\\\n = 6,438.97 \ moles[/tex]
The mass of air in the balloon is calculated as;
[tex]n = \frac{m}{M} \\\\m = nM\\\\m = 6,438.97\ moles \ \times \ 29 \ g/mol\\\\m = 186.73 \ kg[/tex]
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