Question

Calculate the final pressure, in millimeters of mercury, for each of the following, if n and v do not change. Part a: a gas with an initial pressure of 1200 torr at 153 ∘c is cooled to 0 ∘c.

a) 1200 mmHg
b) 1000 mmHg
c) 800 mmHg
d) 600 mmHg

Answer 1

To find the final pressure of a gas cooled from 153 °C to 0 °C with constant volume and moles, one must use the combined gas law. The final pressure, in terms of millimeters of mercury, is calculated to be approximately 767.45 mmHg.

Step-by-step explanation:

The question involves calculating the final pressure of a gas that has been cooled, with the initial and final temperatures provided, using the general gas law. To do this, we will use the combined gas law equation which relates pressure, volume, and temperature of a gas: P1/T1 = P2/T2. Note that the temperatures need to be in Kelvin.

First, let's convert the temperature from Celsius to Kelvin by adding 273.15: T1 = 153 + 273.15 = 426.15 K and T2 = 0 + 273.15 = 273.15 K.

Now, since we are given the initial pressure P1 = 1200 torr, and assuming the volume and moles of gas do not change (n and V are constant), we can find P2 by rearranging the combined gas law equation to P2 = P1 * (T2/T1). Substituting the known values gives P2 = 1200 torr * (273.15 K / 426.15 K).

After performing the calculation, we get P2 approximately equals 767.45 torr, which is the final pressure of the gas in torr. Since 1 torr is equivalent to 1 mmHg, the final pressure in millimeters of mercury is also 767.45 mmHg.