Explore the conditions under which the 'integral' approximation for the translational partition function is not valid by

Question:

Explore the conditions under which the 'integral' approximation for the translational partition function is not valid by considering the translational partition function of an Ar atom in a cubic box of side 1.00 cm. Estimate the temperature at which, according to the integral approximation, q = 10 and evaluate the exact partition function at that temperature.