Calculate the number of moles and the mass of Ar gas present in a 3.00 L steel container if the pressure is 5.75 atm, and the temperature is 22.0 $\degree$C.

Question

Quizplus · Accepted Answer

First, we need to convert the temperature from Fahrenheit to Celsius:

22.0°F = -5.6°C

Next, we use the ideal gas law equation:

PV = nRT

where P is the pressure in atm, V is the volume in L, n is the number of moles, R is the gas constant (0.08206 L·atm/K·mol), and T is the temperature in Kelvin (K = °C + 273.15). We can rearrange this equation to solve for the number of moles:

n = PV/RT

Plugging in the given values:

n = (5.75 atm)(3.00 L)/(0.08206 L·atm/K·mol)(-5.6°C + 273.15)

Note that we need to use the temperature in Kelvin.

n = 0.7116 mol

Next, we can use the molar mass of argon (39.95 g/mol) to find the mass of argon present:

mass = n × molar mass = 0.7116 mol × 39.95 g/mol = 28.41 g

Therefore, the answer is B, 0.712 mol and 28.4 g.

Calculate the Number of Moles and the Mass of Ar °\degree°

Calculate the Number of Moles and the Mass of Ar $\degree$