Although the valence electron pairs in ammonia have a tetrahedral arrangement, the overall geometric structure of the ammonia molecule

geometric-structure
ammonia-molecule

#1

Although the valence electron pairs in ammonia have a tetrahedral arrangement, the overall geometric structure of the ammonia molecule in not described as being tetrahedral. Explain.

Answer:

The ammonia ion has a trigonal pyramidal molecular geometry due to the lone pair of electrons in one of the four possible bonding sites;
NH3 : H
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H–N:
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H