Question

The density of a test gas is to be determined experimentally at 287.2 K using an apparatus constructed of a 3.700 L glass bulb volume that is attached to a vacuum pump. The mass of the evacuated bulb is 24.031 g. After it is filled with the test gas to a pressure of 0.0750 atm, the mass increases to 24.752 g. Assume the gas behaves ideally.

What is the density of the gas? student submitted image, transcription available belowin g/L

Answer 1

To calculate the density of the gas, subtract the weight of the empty bulb from the weight of the full bulb to find the mass of the gas, then use the ideal gas law rearranged for molar mass and finally divide the mass by the volume of the bulb.

Step-by-step explanation:

To calculate the density of the gas, we need to first find the mass of the gas that was added to the bulb. This is found by subtracting the mass of the empty bulb from the mass of the bulb filled with gas. The mass of the gas is 24.752 g - 24.031 g = 0.721 g.

Now, we can use the ideal gas law (PV = nRT) to find the moles of the gas. However, since we're interested in density, we can rearrange the formula to find the molar mass (M), where M = (mRT)/(PV). We have the mass (m), the universal gas constant (R = 0.0821 L·atm/mol·K), the temperature (T = 287.2 K), the pressure (P = 0.0750 atm), and the volume (V = 3.700 L). Plugging in these values, we can calculate the molar mass.

After finding the molar mass, the density (d) can be found by dividing the mass of the gas by the volume of the bulb. Density, d = m/V. So, the density of the test gas is 0.721 g / 3.700 L = 0.195 g/L.