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Chemistry · Structure of atom
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Chemistry · Structure of atom
Consider the following statements regarding stability of subshells:\n(A) Half-filled and fully filled subshells possess extra stability.\n(B) Symmetrical distribution of electrons leads to lower shielding of one electron by another.\n(C) Exchange energy is maximum when the subshell is either half-filled or fully filled.\n(D) Chromium and copper exhibit anomalous electronic configurations due to extra stability of \( d^5 \) and \( d^{10} \) states. \nHow many of the above statements are correct?
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If an atom has an atomic number \( Z = 11 \) and mass number \( A = 23 \), calculate the number of neutrons \( n \) in its nucleus.
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Calculate the specific charge (\( e/m_e \) ratio) of an electron given that its charge is \( -1.602 \times 10^{-19} \text{ C} \) and its mass is \( 9.1094 \times 10^{-31} \text{ kg} \).
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Calculate the energy of an electron in the second stationary state (\( n = 2 \)) of a hydrogen atom (\( R_H = 2.18 \times 10^{-18} \text{ J} \)).
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Given below are two statements: one is labelled as Assertion (A) and the other is labelled as Reason (R).\n Assertion (A): Copper has the outer electronic configuration of \( 3d^{10} 4s^1 \) instead of \( 3d^9 4s^2 \).\n Reason (R): Fully filled and half-filled subshells have extra stability due to high exchange energy and symmetrical distribution. \nIn the light of the above statements, choose the correct answer from the options given below:
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Given below are two statements:\n Statement I: The number of radial nodes in an orbital is given by the expression \( (n - l - 1) \).\n Statement II: The total number of nodes for any orbital is given by \( (n - 1) \). \nIn the light of the above statements, choose the most appropriate answer from the options given below:
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Which isotope of hydrogen is radioactive and found in trace amounts on Earth?
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What is the frequency of emission of neon gas if it produces \( 2 \text{ J} \) of energy and emits a wavelength of \( 616 \text{ nm} \)?
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Which of the following metals listed in Table 2.2 has the lowest work function \( W_0 \)?
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According to the Aufbau principle and \( (n + l) \) rule, what is the correct increasing order of energy for the orbitals \( 3d, 4s, 4p \) and \( 5s \)?
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An atomic species has 18 electrons, 19 protons, and 20 neutrons. What is its correct symbol?
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Given below are two statements: one is labelled as Assertion (A) and the other is labelled as Reason (R). Assertion (A): Unlike sound waves, electromagnetic waves do not require a medium and can move in vacuum. Reason (R): Electromagnetic waves are composed of oscillating electric and magnetic fields perpendicular to each other and to the direction of propagation. In the light of the above statements, choose the correct answer from the options given below:
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Given below are statements about the sub-atomic particles and atomic models: (A) Cathode rays are deflected by electric and magnetic fields in a manner similar to negatively charged particles. (B) The specific charge of cathode ray particles depends on the material of electrodes used. (C) Millikan determined the charge on an electron using the oil drop method. (D) Rutherford's alpha scattering experiment showed that most of the space in an atom is empty. Which of the above statements are correct?
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Consider the following information regarding the four quantum numbers:\n(A) Principal quantum number (\( n \)) determines the size and to a large extent the energy of the orbital.\n(B) Azimuthal quantum number (\( l \)) determines the shape of the orbital.\n(C) Magnetic quantum number (\( m_l \)) determines the total number of subshells in a principal shell.\n(D) Spin quantum number (\( m_s \)) designates the orientation of the spin of the electron. \nHow many of the above statements are correct?
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In a hydrogen atom, which of the following transitions or states corresponds to the ground state energy of the electron?
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Consider the spectral series of hydrogen atom given in the table below. Which series corresponds to an infrared spectral region with \( n_1 = 3 \)? \n| Series | \( n_1 \) | \( n_2 \) | Spectral Region |\n|---|---|---|---|\n| Lyman | 1 | 2, 3... | Ultraviolet |\n| Balmer | 2 | 3, 4... | Visible |\n| Paschen | 3 | 4, 5... | Infrared |\n| Brackett | 4 | 5, 6... | Infrared |
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Given below are two statements: one is labelled as Assertion (A) and the other is labelled as Reason (R). Assertion (A): An absorption spectrum consists of dark lines in an otherwise continuous bright spectrum. Reason (R): Atoms absorb radiation of certain wavelengths from white light, leaving dark spaces. In the light of the above statements, choose the correct answer from the options given below:
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Given below are two statements: one is labelled as Assertion (A) and the other is labelled as Reason (R).\n Assertion (A): The exact position and exact momentum of an electron in an atom cannot be determined simultaneously.\n Reason (R): The product of uncertainties in position and momentum for a microscopic particle is less than \( \frac{h}{4\pi} \). \nIn the light of the above statements, choose the correct answer from the options given below:
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Calculate the number of neutrons in the bromine species \( ^{80}_{35}\text{Br} \).
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What is the maximum capacity of electrons in a subshell with principal quantum number \( n \) based on Pauli's exclusion principle?
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Calculate the de Broglie wavelength associated with a neutron whose wavelength is used as 800 pm in crystal diffraction.
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Which of the following sets of quantum numbers describes an electron experiencing the highest energy in a multi-electron system according to the \( (n + l) \) rule and energy hierarchy?
Read answer →Chemistry · Structure of atom
