Question

An argon laser contains 1200.0 mL of gas at an extremely cold temperature of -100.0°C and a

pressure of .500 atm. How many moles of gas are contained in the laser?

Answer 1

To determine the number of moles of gas in the laser, we can use the ideal gas law:

PV = nRT

where P is the pressure, V is the volume, n is the number of moles, R is the gas constant, and T is the temperature in Kelvin.

First, we need to convert the volume and temperature to units that are compatible with the ideal gas law. We can convert 1200.0 mL to liters by dividing by 1000:

V = 1200.0 mL / 1000 = 1.200 L

We also need to convert the temperature from Celsius to Kelvin by adding 273.15:

T = -100.0°C + 273.15 = 173.15 K

Now we can substitute these values, along with the given pressure of 0.500 atm, into the ideal gas law and solve for the number of moles:

n = PV / RT

n = (0.500 atm)(1.200 L) / (0.0821 L·atm/mol·K)(173.15 K)

n = 0.0358 mol

Therefore, there are 0.0358 moles of gas in the laser