Answer :
Final answer:
The mass of air in the tank can be found using the ideal gas law formula. The calculation involves converting units and plugging in the known values to find the number of moles, which is then multiplied by the average molecular mass of air to obtain the mass of air in the tank. The mass of air is approximately 5.6 kg.
Explanation:
The mass of air contained in the tank can be calculated using the ideal gas law formula: PV = nRT, where P is the pressure, V is the volume, n is the number of moles, R is the ideal gas constant, and T is the temperature.
First, convert the given pressure from MPa to Pa: 7.5 MPa = 7.5 x 10^6 Pa.
Next, rearrange the formula to solve for the number of moles (n): n = (PV) / (RT).
Plug in the known values: P = 7.5 x 10^6 Pa, V = 0.2 m³, R = 8.314 J/(mol·K), and T = 172 K.
Calculate the number of moles, and then multiply by the average molecular mass of air (29 g/mol) to find the mass of air in the tank.
The mass of air in the tank is approximately 5.6 kg, so the correct answer is b) 5.6 kg.
