Find the maximum work done (cal) when 0.5 mol of a gas expands isother...
°C.
First, we need to determine the pressure of the gas using 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.
We are given that n = 0.5 mol, V1 = 2 L, V2 = 5 L, and T = 27°C = 300 K (since we need to use Kelvin in the ideal gas law).
Rearranging the equation, we get:
P = nRT/V
Plugging in the values, we get:
P = (0.5 mol)(0.08206 L·atm/mol·K)(300 K)/(2 L) = 6.123 atm
Now, we can use the formula for work done during an isothermal expansion:
W = -nRT ln(V2/V1)
where W is the work done, n is the number of moles, R is the gas constant, T is the temperature in Kelvin, and ln is the natural logarithm.
Plugging in the values, we get:
W = -(0.5 mol)(0.08206 L·atm/mol·K)(300 K) ln(5/2) = -40.8 cal
Note that the negative sign indicates that work is being done on the system (since the gas is expanding), and the work done is measured in calories (cal).
Therefore, the maximum work done is 40.8 cal.