Describe the difference in structure between beH2 and CaH2

Hello!

BeH₂ is a linear molecule, while CaH₂ is an angular molecule.

The difference between these two molecules is given by the number of electrons they have. Beis in the 2nd period of the Periodic table, and the ion Be⁺² doesn't have any free electron pairs when bonding to H. Ca is in the 4 period of the periodic table, meaning that it has more electrons, and the ion Ca⁺² has two free electron pairs when bonding to H that makes the molecule angular by pushing the bonds at an angle by sterical hindrance.

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