I wrote the answer on this paper and here is the calculations step by step
very sry the "V" must be replaced with 285 and the 285 must be replaced with "V" and the answer is 231.09 cm3. sorry for the inconvenience.
Answer:Hence, the bond length in HCl is 125 pm.
Explanation:
Bond length : It is an average distance between the nuclei of two bonded atoms in a molecule.
Also given that bond length is the distance between the centers of two bonded atoms. on the potential energy curve, the bond length is the inter-nuclear distance between the two atoms when the potential energy of the system reaches its lowest value. Beyond this if atoms come closer to each other then their will be repulsion between them.
So, the bond length between the Hydrogen and Chlorine atom in HCl molecule is :

Hence, the bond length in HCl is 125 pm.