I am not sure how to approach this problem and why this is correct answer
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In ammonia NH3 we have hybridizising. The s and the 3 p orbitals form a new Orbital sp3.
Nitrogen has 5 electrons to put in, so each H overlap with his s Orbital to the sp3 Orbital to get the 8 electrons for octett. One of it carries the lone pair  from nitrogen.

Quote from: ann on October 28, 2022, 09:25:25 PM
I am not sure how to approach this problem and why this is correct answer

In ammonia, N has four groups means 3 atoms and one sigma bond and it is sp3 hybridized .Three sp³ hybridized orbitals are making three sigma bond with 1s orbital of H and one sp³ hybridized orbital is accommodating lone pair.
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