Bond angle in H2O is explained by            theory and bond angle in H2S , H2Se , H2Te  is explained by

In H2O molecule , Oxygen atom has four electron pairs around it According to VSEPR theory, shape must be tetrahedralBut due to lp-lp repulsions bond angle decreases to 104.5oAnd  water molecule is bent (or) angularIn H2S , H2Se , H2Te , H2Po  the bond angle is around 90-93oIt is assumed that p-orbitals of central atom participate in bonding P-orbitals are 90o  to each other , the bond angle is around  90o - 93oThus VBT explains the shapes of  H2S , H2Se , H2Te , H2Po