Atomic Structure
Topics
- Electromagnetic radiation, photoelectric effect, hydrogen spectrum
- Bohr model and its limitations
- Dual nature of matter, de Broglie relation, Heisenberg uncertainty principle
- Quantum mechanical model, orbitals, psi and psi-squared plots
- Quantum numbers and shapes of s, p, d orbitals
- Aufbau, Pauli and Hund's rule, electronic configuration, half-filled/filled stability
Chapter tests
See all →Top questions
See all →- Energy and radius of first Bohr orbit of He^+ and Li^2+ are[Given R_H = 2.18×10^-18 J, a_0 = 52.9 pm] Answer: 1. E_n(mathrmLi²⁺) = -19.62×10⁻¹⁸ J; r_n(mathrmLi²⁺) = 17.6 pm; E_n(He^+) = -8.72×10⁻¹⁸ J; r_n(He^+) = 26.4 pm Key idea: for hydroge... 1
- The ratio of the wavelengths of the light absorbed by a Hydrogen atom when it undergoes n=2 → n=3 and n=4 → n=6 transitions, respectively, is Answer: 4. 1/4 Key idea: absorbed wavelength is inversely proportional to the energy gap, 1/λ∝(1/n₁²-1/n₂²) . For 2→3 : 1/4-1/9=5/36 , so λ₁... 1
- The energy of an electron in the ground state (n = 1) for He^+ ion is -x J, then that for an electron in n = 2 state for Be^3+ ion in J is : Answer: 2. -x Key idea: for hydrogen-like ions E_n=-E₁(H) Z²/n² . For He^+ (Z=2), n=1: -x=-4E₀ , so E₀=x/4 . For mathrmBe³⁺ (Z=4), n=2: E=-E... 1
- Match List I with List II.List I (Quantum Number): A. m_l B. m_s C. l D. nList II (Information provided): I. shape of orbital II. size of orbital III. orientation of orbital IV. orientation of spin of electronChoose the correct answer from the option… Answer: 3. A-III, B-IV, C-I, D-II Key idea: each quantum number gives one property of the electron or orbital. m_l : orientation of the orbi... 1
- Select the correct statements from the following :A. Atoms of all elements are composed of two fundamental particles.B. The mass of the electron is 9.10939 × 10^-31 kg.C. All the isotopes of a given element show same chemical properties.D. Protons an… Answer: 1. B, C and E only Key idea: Check each statement. A. False: atoms are made of three fundamental particles (electron, proton, neutro... 1
- The relation between n_m, (n_m = the number of permissible values of magnetic quantum number (m)) for a given value of azimuthal quantum number (l), is Answer: 2. l = n_m - 1/2 Key idea: For a given l , m takes values from -l to +l including 0. Number of values: n_m = 2l + 1 . Rearranging, l... 1