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Question
The mass of a neutral carbon atom in ground state is
Options
exact 12 u
less than 12 u
more than 12 u
depends on the form of carbon such as graphite of charcoal.
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Solution
exact 12 u
In nuclear physics, a unit used for measurement of mass is unified atomic mass unit, which is denoted by u.
It is defined such that
1 u = `1/12 xx` (Mass of neutral carbon atom in its ground state)
Mass of neutral carbon atom in its ground state = 12 × 1 u = 12 u
Thus, the mass of neutral carbon atom in its ground state is exactly 12 u.
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