Calculating the Number of Molecules of Gas in a Sample

How many molecules of gas are in the sample?

The correct answer is 5.76 x 10²¹ molecules.

Explanation

The problem states that a sample of carbon dioxide is contained in a 250.0 mL flask at 0.917 atm and 19.3 ∘C. To find the number of molecules of gas in the sample, we can use the ideal gas law equation PV = nRT. Given data: - Volume (V) = 250.0 mL = 0.25 L - Pressure (P) = 0.917 atm - Temperature (T) = 19.3 ∘C = 292.3 K First, we need to calculate the number of moles of gas (n): n = PV/RT n = (0.917 atm x 0.25 L) / (0.082 L.atm/K.mol x 292.3 K) n = 9.6 x 10⁻³ mol Next, we know that 1 mol of any compound is equal to 6.022 x 10²³ molecules of the compound. Therefore, we can convert moles to molecules using this ratio: 9.6 x 10⁻³ mol x 6.022 x 10²³ molecules / 1 mol = 5.76 x 10²¹ molecules So, there are 5.76 x 10²¹ molecules of gas in the sample.
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