Beta Decay

Q. A positron is emitted from ${}_{11}^{23}Na$. The ratio of the atomic mass and atomic number of the resulting nuclide is:

1. $\frac{22}{10}$
2. $\frac{23}{10}$
3. $\frac{23}{12}$
4. $\frac{22}{11}$

Q. ${}_{13}^{27}Al$ is a stable isotope. ${}_{13}^{29}Al$ is expected to decay by :

1. $\alpha -$ emission
2. $\beta -$ emission
3. Positron emission
4. Proton emission

Q. Two radioactive elements P and Q have decay constants 21λ₀ and λ_0­ respectively. If initially they have same number of nuclei, then after time $\frac{1}{10{\lambda }_0}$ the ratio of undecayed nuclei of P to undecayed nuclei of Q is

दो रेडियोएक्टिव तत्वों P तथा Q के क्षय नियतांक क्रमशः 21λ₀ तथा λ₀ हैं। यदि प्रारम्भ में इनमें नाभिकों की संख्या समान हो, तो $\frac{1}{10{\lambda }_0}$ समय बाद P के अक्षयित नाभिकों तथा Q के अक्षयित नाभिकों का अनुपात है

1. $\frac{1}{e}$
2. $\frac{1}{e^2}$
3. $\frac{1}{e^4}$
4. e²

Q. ${}^{23}Na$ is the more stable isotope of Na. Find out the process by which ${}_{11}^{24}Na$ can undergo radioactive decay.

1. ${\beta }^{-}-$ emission
2. $\alpha -$ emission
3. ${\beta }^{+}-$ emission
4. $K-$ electron capture

Q. If a Calcium atom with atomic number 20 and mass number 41 undergoes a ${\beta }^{-}$
(beta minus).
The value of Z is ___ and A is ___ in the daughter nucleus.

Q.

A positron is emitted from ${}_{11}N{a}^{24}.$ The ratio of the atomic mass and atomic number of the resulting nuclide is

(IIT-JEE, 2007)

1. 22/10
2. 22/11

3. 23/10

4. 23/12

Q. What happens in a ${\beta }^{+}$ (beta positive) decay?

1. Proton converts into a neutron.
2. Neutron converts into a proton.
3. Electron and antineutrino are created.
4. Positron and neutrino are created.

Q. Bombardment of aluminium by $\alpha -$ particle leads to its artificial disintegration in two ways. (i) and (ii) as shown. Products X, Y and Z respectively are :

1. Proton, neutron, positron
2. Neutron, positron, proton
3. Proton, positron, neutron
4. Positron, proton, neutron

Q. A sample of $H_2{O}_2$ labelled as $25\%$ (w/w) has a density of $1.25\text{g/mL}$. Which among the following correctly represents its concentration?
i. Molarity $=9.2\text{M}$
ii. Molality $=9.8\text{m}$
iii. $\%$ w/V $=33.6\%$
iv. ppm (w/w) $=2500\text{ppm}$

1. i, iii
2. i, ii, iii
3. ii, iii, iv
4. i, ii

Q. Which of the following concentration factor is affected by change in temperature?

Q. ${}_{13}^{27}Al$ is a stable isotope. ${}_{13}^{29}Al$ is expected to decay by :

1. $\alpha -$ emission
2. $\beta -$ emission
3. Positron emission
4. Proton emission