Question

At the start of this experiment your vessel will be evacuated. The precision (readability) of your balance is 1 mg, this means masses below 0.5 mg read as zero. Suppose the volume of the vessel is 0.6L and temperature is 30°C. Assuming ideal gas law conditions, what is the maximum pressure in a vessel containing CO2belowwhichmass cannot be detected?

Answer 1

Answer:

4.55x10⁻⁴ atm

Explanation:

When the balance is used, it first must be tared, it means that the weight of the vessel will be discounted, so the mass of the gas produced must be above 0.5 mg to be read in the balance.

The molar mass of the CO2 is 44 g/mol, so, for a mass of 0.5 mg = 0.0005 g, the number of moles is:

n = 0.0005/44

n = 0.000011 mol

The ideal gas law is:

PV = nRT

Where P is the pressure, V is the volume, R is the constant of the gases (0.082 atm.L/mol.K), and T is the temperature (30°C = 303 K), so:

P*0.6 = 0.000011*0.082*303

P = 4.55x10⁻⁴ atm