Mass number is equal to the sum of number of neutrons (neutral subatomic particle) and number of protons (positively charge particle).
Mass number =
Now, atomic number is same as the number of protons i.e. atomic of nitrogen is 7 . Thus, number of protons is also equal to 7.
Therefore,
Mass number =
=
Hence, mass number of nitrogen is equal to .
The cyclo-heptatrienyl anion will be considered as antiaromatic compound.
A cyclic compound with a greater energy electron system due to the existence of a 4n delocalized electron is what makes up an anti-aromatic chemical.
Due to its eight pi electrons, the cycloheptatrienyl anion (also known as the tropylium anion) should be antiaromatic; yet, the extra lone pair on one carbon could enable that carbon to become hybridized, placing the extra electrons in an
orbital. It would become non-planar as well as non-aromatic as a result.
Therefore, the cyclo-heptatrienyl anion will be considered as antiaromatic compound.
To know more about antiaromatic compound.
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