Answer:
The hydrogen atoms in ammonia orient themselves as far away as possible from each other because this arrangement minimizes repulsion between electron groups present in the molecule
Step-by-step explanation:
A covalent bond is formed between two atoms when a pair of electrons is shared between two atoms. This forms an electron group which occupies the the space between the atoms. Similarly, a lone pair of electrons defines an electron group that is located primarily on one atom.
An ammonia molecule is made up of three hydrogen atoms covalently bonded to a central nitrogen atom. The electron groups in an ammonia molecule consists of a lone pair of electrons found on the nitrogen atom alone and three bonding pairs of electrons shared between the nitrogen and hydrogen atoms.
According to the VSEPR (valence shell electron pair repulsion) theory, since electron groups are negatively charged regions, they repel one another. Therefore,the best arrangement of a given number of electron groups is the one that minimizes the repulsion among them.
In accordance with the VSEPR theory, the hydrogen atoms in ammonia orient themselves as far away as possible from each other because this arrangement minimizes repulsion between electron groups present in the molecule.