CBSE Class 11 (Science) Atomic Structure — practice questions
107 free MCQs with worked solutions. Tap any question for the answer + explanation, or practice them all in the app.
Practice CBSE Class 11 (Science) Atomic Structure in the app →The wave number $\bar{\nu}$ of electromagnetic radiation is defined asIn vacuum, the velocity of electromagnetic radiation isA photon has wavelength $400\,nm$. Its frequency is approximatelyThe wave number of a photon of frequency $6 \times 10^{14}\,Hz$ (in vacuum) isAccording to Planck's quantum theory, energy is emitted or absorbed in discrete packets calledThe energy of a photon of wavelength $\lambda$ is given byA photon of wavelength $300\,nm$ has approximately what energy in eV? (Use $hc = 1240\,eV\,nm$.)In the photoelectric effect, the kinetic energy of the ejected electron depends onThe threshold frequency $\nu_0$ for a metal is the minimum frequencyLight of frequency $\nu = 2\nu_0$ ejects photoelectrons from a metal with threshold frequency $\nu_0$. The maxRutherford's $\alpha$-particle scattering experiment used a thin foil of which metal?For a hydrogen-like atom of nuclear charge $Z$, the radius of the $n$th Bohr orbit scales asThe energy of the $n$th Bohr orbit of a hydrogen-like atom isThe ratio of the radii of the third Bohr orbit of $He^+$ and the first Bohr orbit of $H$ isThe velocity of the electron in the $n$th Bohr orbit of a hydrogen-like atom is proportional toThe energy required to remove the electron from the first excited state ($n=2$) of $He^+$ isWhich series of the hydrogen spectrum lies entirely in the *visible* region?Rydberg's formula for the wave number of a hydrogen spectral line isThe longest wavelength line in the Lyman series of hydrogen corresponds to the transitionThe de Broglie wavelength of a particle of mass $m$ and momentum $p$ isThe de Broglie wavelength of an electron in the $n$th Bohr orbit, in terms of the orbit radius $r_n$, isAn electron is accelerated through a potential difference of $100\,V$. Its de Broglie wavelength is approximatHeisenberg's uncertainty principle relates the uncertainties in position and momentum asThe minimum uncertainty in the velocity of an electron whose position is known to within $\Delta x = 0.1\,nm$ The principal quantum number $n$ can take valuesFor principal quantum number $n$, the orbital quantum number $l$ takes valuesFor orbital quantum number $l$, the magnetic quantum number $m_l$ takes valuesHow many orbitals are present in the $n = 3$ shell?The maximum number of electrons in the subshell with $n = 4, l = 2$ isWhich set of quantum numbers $(n, l, m_l, m_s)$ is **NOT** allowed?Hund's rule applies during the filling ofThe Aufbau principle dictates that orbitals fill in order of increasingWhich of the following orbital shapes is dumbbell-shaped along an axis?How many *angular* nodes does a $3d$ orbital have?The number of *radial* nodes in a $4s$ orbital isThe ionisation energy of hydrogen in its ground state isFor $He^+$, the ionisation energy from its ground state isWhich transition in the hydrogen atom emits the largest amount of energy?Which of the following experimental phenomena could **NOT** be explained by classical EM wave theory?The Bohr model failed to explainIn the photoelectric effect, the *stopping potential* $V_0$ varies with the frequency of incident light asWhich of the following is **NOT** a possible set of quantum numbers for a 3d electron?The total number of electrons that can fit in the $M$ shell ($n=3$) isThe Bohr radius for hydrogen ($n=1, Z=1$) is approximatelyThe proton was discovered through experiments involvingThe neutron was discovered byIn Thomson's atomic model (plum-pudding), the atom isThe Bohr orbit velocity of the ground-state electron in hydrogen is aboutThe Rydberg constant for hydrogen, in SI units, isAs per your syllabus, using ³⁵Cl (75.77%, mass 34.9689) and ³⁷Cl (24.23%, mass 36.9659), what is the AVERAGE AAs per your syllabus, what is the MOLECULAR MASS of methane (CH₄) — using C = 12.011 u and H = 1.008 u?As per your syllabus, what is the MOLECULAR MASS of glucose (C₆H₁₂O₆) — using C=12.01, H=1.008, O=16.00?As per your syllabus, what is the molar mass of WATER (H₂O)?As per your syllabus, what is the molar mass of SODIUM CHLORIDE (NaCl)?As per your syllabus, the charge-to-mass ratio e/m_e of the electron, measured by J.J. Thomson in 1897, is whiAs per your syllabus, which experiment determined the charge on the electron as −1.602 × 10⁻¹⁹ C?As per your syllabus, which of the following is the correct mass of the electron derived from Millikan's e andAs per your syllabus, which fundamental particle has approximate mass 1.674927 × 10⁻²⁷ kg and zero charge?As per your syllabus, the smallest and lightest positive ion (a proton) was obtained from which gas in modifieAs per your syllabus, which pair of nuclides represents ISOBARS (same A, different Z)?As per your syllabus, a species with 18 electrons, 16 protons, and 16 neutrons has what symbol?As per your syllabus, in Rutherford's α-scattering on a gold foil, approximately how many α-particles bounced As per your syllabus, the radius of the first Bohr orbit of hydrogen (n = 1) — the Bohr radius a₀ — is approxiAs per your syllabus, what is the energy of the first orbit of He⁺ (Z = 2, n = 1)?As per your syllabus, eqn 2.15, the radius of the n-th Bohr orbit for a hydrogen-like ion (one electron, atomiAs per your syllabus, in the hydrogen-atom spectrum the BALMER series corresponds to transitions ending in n₁ As per your syllabus, eqn 2.9, the Rydberg formula for all spectral lines in hydrogen uses a constant value ofAs per your syllabus, eqn 2.5, the relation between the frequency ν, wavelength λ, and the speed of light c inAs per your syllabus, what is the energy of one mole of photons of radiation of frequency 5 × 10¹⁴ Hz?As per your syllabus, the LYMAN series (n₁ = 1) of hydrogen lines lies in which spectral region?As per your syllabus, eqn 2.22, the de Broglie wavelength λ of a particle of momentum p (or mass m, velocity vAs per your syllabus, the magnetic quantum number m_l takes how many values for a given azimuthal quantum numbAs per your syllabus, for n = 3 the TOTAL number of orbitals is which value?As per your syllabus, the electron-spin quantum number m_s — introduced by Uhlenbeck and Goudsmit (1925) — takAs per your syllabus, the TOTAL number of nodes in an orbital (radial + angular) is given by which formula?A 3p orbital is specified by:The shape of a p-orbital is best described as:Isotopes have the SAME number of:The energy of the nth orbit in a hydrogen atom (Bohr's model) is:The de Broglie wavelength of a particle with momentum p is:Heisenberg's uncertainty principle is most accurately stated as:Hund's rule states that electrons in degenerate orbitals:By the AUFBAU principle, the 3d subshell starts filling:The electronic configuration of Cr (Z=24) is an exception, written as:In the photoelectric effect, the kinetic energy of ejected electrons is:The charge carried by an electron is about:The proton was characterised in the year:Who discovered the neutron?The neutron was discovered in the year:Chadwick bombarded a thin sheet of which element?Chadwick bombarded that sheet with:Compared with a proton, the mass of a neutron is:In Thomson's model, the positive charge of the atom is:Thomson's model is popularly nicknamed the:Thomson was awarded the Nobel Prize for physics in:How many quantum numbers designate each orbital?The principal quantum number determines the size and largely the:The number of allowed orbitals in a shell is given by:How many sub-shells does the second shell contain?How many sub-shells does the third shell contain?The sub-shell notation for l equal to 0 is the:The sub-shell notation for l equal to 2 is the:The Pauli exclusion principle was given by a scientist from:Pauli stated his exclusion principle in:Pauli's principle says no two electrons in an atom can share the same set of:Two electrons occupying the same orbital must have:Hund's rule is known as the rule of maximum: