In the HCl molecule the separation between the nuclei of the two atoms

Dhanalakshmi · July 3, 2019, 12:05pm

In the HCl molecule the separation between the nuclei of the two atoms is about 1.27Angstrom.find

Dhanalakshmi · July 3, 2019, 12:07pm

Let x axis be along the distance between the two atoms, and hydrogen atom be at origin.
Then,
X_cm = (m_H(0) + m_Cl(1.27))/(m_H + m_Cl)
= m_Cl(1.27)/(m_H + m_Cl)
= 35.5_mH (1.27)/(m_H + 35.5m_H )
= 35.5x1.27/36.5
= 1.235 A
Hence the centre of mass is 1.235 A from the hydrogen atom along the line joining the two atoms.