An ab4 molecule has two lone pairs of electrons on the a atom (in addition to the four b atoms). what is the electron-domain geometry around the a atom?

Answer : The electron-domain geometry around the 'A' atom is, octahedral.

Explanation :  

As per given in the question, an has two lone pairs of electrons on the atom 'A' and four number of monovalent atoms (B) are bonded to the central atom.

That means, the total number of electrons pairs = 2 + 4 = 6

The number of electrons pairs is 6 that means the hybridization will be and the electronic or electron domain geometry of the molecule will be octahedral.

The electron domain geometry is also shown below.

Hence, the electron-domain geometry around the 'A' atom is, octahedral.

sodium (na), for example, has one electron in its valence shell. this is an unstable state because that valence shell needs eight electrons to be full. in order to fill its valence shell, find a way to add seven electrons to its valence shell

sorry idk the answer well to you i have a explaination

explanation: a formula which shows the arrangement of atoms in the molecule of a compound