The Lewis diagram for BH2 is: [H-B-H]-
The electron- pair geometry around the B atom in BH2 is:.
There arelone pair(s) around the central atom, so the geometry of BH2 is .

The geometry of the electron pair around the Boron atom in is called the trigonal planar. In this case, there is a pair of isolated electrons around Boron, which is the central atom, allowing the molecule to have a folded geometry.

We can arrive at this answer because:

This allows for a folded geometry around the molecule, allowing Boron to be an exception to the octet rule and achieve stability with 5 electrons in the valence layer.

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Electron pair geometry- trigonal planar

There is one lone pair around the boron atom

The geometry of BH2 is bent

Explanation:

The valence shell electron pair repulsion theory offers a frame work for determining the shape of molecules based on the number of electron pairs of the valence shell of the central atom in the molecule.

In BH2-, the central atom is boron. There is a lone pair on boron. Owing to the lone pair on boron, the molecular geometry of BH2 is bent.

1 is the answer to this problem