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Q.
$ C^{14}$ is
AFMCAFMC 2011
Solution:
Carbon has three important isotopes $C ^{12}, C ^{13}$ and $C^{14} \cdot C^{14}$ is formed as traces in the atmosphere by cosmic neutron bombardment of nitrogen
${ }_{7} N ^{14}+{ }_{0} n^{1} \longrightarrow { }_{6} C ^{14}+{ }_{1} H ^{1}$
$C ^{14}$ is a natural radioactive isotope.