Number of α and β emitted in the reaction, ₉₂U²³⁸ → ₈₂Pb²⁰⁶ are

• 6α and 8β

• 8α and 6β

• 6α and 4β

• 4α and 6β

Which of the following can be used to convert ${}_7{}^{14}\mathrm{N}$ into ${}_8{}^{17}\mathrm{O}$?

• Deutron

• Proton

• α-particle

• Neutron

Which of the following describes the shape of orbital?

• Principal quantum number

• Azimuthal quantum number

• Magnetic quantum number

• Spin quantum number

154.

For an electron impossible combination of quantum number is

• n = 3; l = 2; m_l = -2; m_s = +$\frac{1}{2}$

• n = 3; l = 2; m_l = -3; m_s = +$\frac{\mathrm{}}{$ \frac{1}{2}$}$

• n = 4; l = 0; m_l = 0; m_s = -$\frac{1}{2}$

• n = 5; l = 3; m_l = 0; m_s = -$\frac{1}{2}$

The energy of an electron in n^th orbit of hydrogen atom is

• $\frac{13.6}{{\mathrm{n}}^4}\mathrm{eV}$

• $\frac{13.6}{{\mathrm{n}}^3}\mathrm{eV}$

• $-\frac{13.6}{{\mathrm{n}}^2}\mathrm{eV}$

• $\frac{13.6}{\mathrm{n}}\mathrm{eV}$

Which of the following is not iso-electronic?

• Na⁺

• Mg²⁺

• O^2-

• Cl^-

Which of the following equations represent de-Broglie relation?

• $\frac{\mathrm{h}}{\mathrm{mv}}=\mathrm{p}$

• $\mathrm{\lambda m} =\frac{\mathrm{v}}{\mathrm{p}}$

• $\mathrm{\lambda }=\frac{\mathrm{h}}{\mathrm{mp}}$

• $\mathrm{\lambda }=\frac{\mathrm{h}}{\mathrm{mv}}$

Which of the following sequences of the energy levels of the subshells related to principal quantum number four (n = 4)?

• s< p< d< f

• s< d< p< f

• s< f< p< d

• p< s< d< f

The correct electronic configuration of iron is

• 1s², 2s² 2p⁶,3s² 3p⁶, 4s², 3d⁶

• 1s², 2s² 2p⁶,3s² 3p⁶, 4s², 3d⁵

• 1s², 2s² 2p⁶,3s² 3p⁶, 4s², 3d⁷

• 1s², 2s² 2p⁶,3s² 3p⁶, 4s², 3d⁵

Which of the electronic shell of the following elements is not rounded?

• He

• Be

• B

• Li