A rigid 10.0 L flask contains two gases at 300 K: 2.00 g of H and 8.00 g of Ar
CHEMISTRY · Multi-part · A Level · Chemistry · Amount of substance · Amount of substance
Problem
A rigid 10.0 L flask contains two gases at 300 K: 2.00 g of H2 and 8.00 g of Ar. The flask is fitted with a stopcock that allows additional argon to be injected without changing the volume. After an additional 5.00 g of Ar is introduced, the flask is heated to 450 K and allowed to re-equilibrate.
(a) Calculate the total pressure in the flask before any argon is added.
(b) Determine the mole fraction of hydrogen in the initial mixture.
(c) After the 5.00 g of Ar is added and the temperature is raised to 450 K, compute the new total pressure in the flask.
(d) Calculate the partial pressure of hydrogen after the temperature increase and argon addition. Explain whether this value is greater than, less than, or equal to the hydrogen partial pressure calculated in part (a), and justify your answer based on quantitative reasoning.