A plot of the number of neutrons (N) against the number of protons (P) of stable nuclei exhibits upward deviation from linearity for atomic number, Z 20. For an unstable nucleus having N / P ratio less than 1, the possible mode(s) of decay is (are)

Question

A plot of the number of neutrons (N) against the number of protons (P) of stable nuclei exhibits upward deviation from linearity for atomic number, Z > 20. For an unstable nucleus having N / P ratio less than 1, the possible mode(s) of decay is (are) (A) β-decay ( β emission) (B) orbital or K-electron capture (C) neutron emission (D) β+decay ( positron emission)

Tardigrade Admin · Accepted Answer

A nucleus whose low n / p ratio place it below the belt of stability either emits positrons or undergo electron capture eg 611 C longrightarrow 511 B + +10 e (Positron emission) eg. 56133 Ba + -10 e longrightarrow 55133 Cs + X-ray

Q. A plot of the number of neutrons $(N)$ against the number of protons $(P)$ of stable nuclei exhibits upward deviation from linearity for atomic number, $Z > 20$ . For an unstable nucleus having $N / P$ ratio less than 1, the possible mode(s) of decay is (are)

$β^{-}$ decay ( $β$ emission)

orbital or $K -$ electron capture

neutron emission

$β^{+}$ decay ( positron emission)

A nucleus whose low $n / p$ ratio place it below the belt of stability either emits positrons or undergo electron capture
eg $_{6}^{11} C ⟶_{5}^{11} B +_{+ 1}^{0} e$ (Positron emission)
eg. $_{56}^{133} B a +_{- 1}^{0} e ⟶_{55}^{133} C s + X$ -ray

Q. A plot of the number of neutrons (N) against the number of protons (P) of stable nuclei exhibits upward deviation from linearity for atomic number, Z>20. For an unstable nucleus having N/P ratio less than 1, the possible mode(s) of decay is (are)

β−decay ( β emission)

orbital or K−electron capture