Step 1: Electronic Configuration of Pr\(^{3+}\).
Praseodymium (Pr) has atomic number 59. Its electronic configuration is: \[\text{Pr:} [Xe] 4f^3 6s^2\]Removing three electrons to form \( \text{Pr}^{3+} \) results in the configuration \( 4f^3 \).
Step 2: Term Symbol Calculation.
For \( 4f^3 \): the total spin quantum number (\( S \)) is 3/2, and the total orbital quantum number (\( L \)) is 3 (denoted as H). The multiplicity is \( 2S+1 = 2(3/2) + 1 = 4 \). Therefore, the term symbol is \( ^4H_5 \).
Step 3: Conclusion.
The ground state term symbol for Pr\(^{3+}\) is \( ^4H_5 \), corresponding to option (3).
Calculate \( \Lambda_m^0 \) for acetic acid and its degree of dissociation (\( \alpha \)) if its molar conductivity is 48.1 \( \Omega^{-1} \, \text{cm}^2 \, \text{mol}^{-1} \).
Given that
\( \Lambda_m^0 (\text{HC}) = 426 \, \Omega^{-1} \, \text{cm}^2 \, \text{mol}^{-1} \),
\( \Lambda_m^0 (\text{NaCl}) = 126 \, \Omega^{-1} \, \text{cm}^2 \, \text{mol}^{-1} \),
\( \Lambda_m^0 (\text{CH}_3\text{COONa}) = 91 \, \Omega^{-1} \, \text{cm}^2 \, \text{mol}^{-1} \).
Europium (Eu) resembles Calcium (Ca) in the following ways:
(A). Both are diamagnetic
(B). Insolubility of their sulphates and carbonates in water
(C). Solubility of these metals in liquid NH3
(D). Insolubility of their dichlorides in strong HCI
Choose the correct answer from the options given below: