This question already has an answer here:
H2O has two lone pair electron and H2S also have two lone pair electron but Bond Angle in H2O is 104.5° but H2S has 92.12°bond Angle .
Both H2O and H2S has same hybridization ,which is sp3 and i know that the four hybrid orbitals of sp3 hybridization are directed towards the four corner of a regular tetrahedron making Angle of 109.5° .
My teacher taught me that for every lone pair you have to subtract 2.5° from 109.5° so if that's the case then both of them should have same Angle as both of them have 2 lone pair electron ? If that's not the case then what is the exact way to determine Bond Angle ? And the way my teacher taught me is it ok ?