The molar mass of the unknown gas in the 500 mL flask at stp is 89.7 g/mol
We'll begin by calculating the number of mole of the gas that occupied 500 mL at stp.
Recall at stp:
22400 mL = 1 mole of the gas
Therefore,
500 mL = 500 / 22400 = 0.0223 mole of gas.
Finally, we shall determine the molar mass of the gas. This can be obtained as follow:
Mass of gas = 2 g
Mole of gas = 0.0223 mole
Molar mass = mass / mole
Molar mass of gas = 2 / 0.0223
Therefore, the molar mass of the unknown gas is 89.7 g/mol
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