Since PF3 and SBr2 both have lone pairs of electrons on the central atom, their bond angles should deviate from the idealized bond angle as lone pairs are more repulsive than bonding pairs of electrons. Large atoms, such as Cl or Br, will cause bond angles to deviate from the ideal, and the presence of a multiple bond will cause a deviation as well owing to the increased electron density, so CH3Br should deviate from the idealized bond angle. BCl3 has identical atoms symmetrically surrounding a central atom with no lone pairs on it, so BCl3 should not deviate from the idealized bond angle.
