IBPhysicsHLExam QuestionsNuclear & Quantum PhysicsStructure of the Atom

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Structure of the Atom (HL IB Physics)

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Structure of the Atom

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Structure of the Atom

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1
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Excitation is

  • When an electron is removed from or added to an atom

  • When an electron transitions from a higher energy level to a lower energy level by emitting a photon

  • When an electron transitions from a lower energy level to a higher energy level by absorbing a photon

  • When an electron in the ground state absorbs just enough energy to leave the atom

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2
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The diagram below shows the energy levels of a mercury atom.

Which transition produces a photon with the longest wavelength?

7-1-discrete-energy--radioactivity-sl-mcqs-easy-q2-question-diagram-2

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    3
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    The diagram shows an energy–level diagram for a hydrogen atom.

    7-1-discrete-energy--radioactivity-sl-mcqs-easy-q3-question-diagram

    How many discrete photon energies could be produced from these energy levels?

    • 3

    • 5

    • 6

    • 7

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    4
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    Which of the following is not a feature of an emission spectrum?

    • Each line corresponds to a specific wavelength of a photon emitted when an electron de-excites

    • An emission spectrum contains a set of discrete wavelengths, represented by coloured lines on a black background

    • An emission spectrum is evidence that electrons in atoms can only transition between discrete energy levels

    • An emission spectrum contains a set of discrete wavelengths, represented by dark lines on a coloured background

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    5
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    Which of the following was not an observation made in Rutherford's scattering experiment?

    • Most of the α-particles went straight through the foil

    • Some α-particles deflected through small angles of less than 10°

    • Only a small number of α-particles deflected straight back at angles greater than 90°

    • The gold foil emits alpha particles

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    6
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    Which of the following statements about nuclear radius is incorrect?

    • The greater the number of nucleons in a nucleus, the greater its radius

    • The radius of a nucleus depends on its proton number

    • The exact relationship between the radius and nucleon number can be determined from experimental data

    • A nucleus containing one proton would have a radius of R0

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    7
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    What do the deviations from the Rutherford scattering give evidence for?

    • The nuclear radius

    • The charge on the nucleus

    • Electric repulsive forces

    • Strong nuclear force

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    8
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    What is the radius of a nucleus of cobalt-27?

    • 3.6 fm

    • 10.8 fm

    • 27 fm

    • 32.4 fm

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    9
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    The emission spectrum of hydrogen can be divided into different 'series' representing photons emitted in the infrared, visible and ultraviolet regions of the electromagnetic spectrum.

    7-1-discrete-energy--radioactivity-sl-mcqs-easy-q5-question-diagram

    Which hydrogen series corresponds to the highest energy photons being emitted?

    • Lyman series

    • Balmer series

    • Brackett series

    • Pfund series

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    10
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    Which of the following statements about nuclear density is correct?

    • The density of a nucleus does not depend on its radius

    • The density of a nucleus depends on its mass number

    • The density of a nucleus is inversely proportional to its radius cubed

    • The density of a nucleus increases as the radius increases

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    1
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    In the Geiger-Marsden-Rutherford experiment, alpha particles are fired at a thin gold foil. Two key observations of the experiment are 

    1. most alpha particles pass through the foil undeflected
    2. a few alpha particles are deflected by large angles

    Which of the following rows correctly explains these observations?

      I. II.
    A. most α-particles miss the gold atoms gold atoms are mostly empty space
    B. the atom is mostly empty space so most α-particles do not interact with the nucleus the nucleus is small, dense and positively charged
    C. the charge on the nucleus is insufficient to cause deflection gold nuclei are small compared to the atom
    D. most α-particles have enough energy to pass through the atom without interacting with it the charge on the nucleus is insufficient to cause large angle deflection

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      2
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      The energy levels of an atom are shown in the diagram below.

      q15_discrete-energy-_-radioactivity_ib-sl-physics-mcq

      Which transition will emit the photon with the shortest wavelength?

      • n = 4 to n = 1

      • n = 2 to n = 1

      • n = 2 to n = 1

      • n = 4 to n = 3 

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      3
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      Hydrogen atoms feature energy levels as shown below.

      q19_discrete-energy-_-radioactivity_ib-sl-physics-mcq

      Which photon energy will not cause an electron to be excited or ionised in a ground state hydrogen atom?

      • 10.2 eV

      • 12.29 eV

      • 12.75 eV

      • 15.0 eV

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      4
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      The following is an energy level diagram for an atom. Electron transitions give rise to emission of spectrum wavelengths λ1, λ2, λ3, λ4, λ5.

      q14_energy-levels-_-photon-emission_aqa-as-physics-mcq

      With reference to the diagram, which of the following statements is correct?

      • E subscript 3 space greater than space E subscript 2 space greater than space E subscript 5 space greater than space E subscript 1 space greater than space E subscript 4

      • f subscript 4 space greater than space space f subscript 5 space greater than space f subscript 1 space greater than space f subscript 2 space greater than space f subscript 3

      • lambda subscript 3 space greater than space lambda subscript 2 space greater than space lambda subscript 1 space greater than space lambda subscript 5 space greater than space lambda subscript 4

      • lambda subscript 4 space greater than space lambda subscript 5 space greater than space lambda subscript 1 space greater than space lambda subscript 2 space greater than space lambda subscript 3

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      5
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      Deviations from Rutherford scattering are observed in experiments carried out at particular energies.

      Which of the following changes to the nucleon number of the target nucleus and the speed of alpha particles would give the greatest deviation from the Rutherford scattering predictions?

        nucleon number of target nucleus speed of alpha particle
      A. decrease increase
      B. decrease decrease
      C. increase increase
      D. increase decrease

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        6
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        Nucleus straight X has radius r and nucleon number A.

        Nucleus Y has radius 3 r and nucleon number 5 over 3 A.

        What is the ratio of fraction numerator d e n s i t y space o f space straight X over denominator d e n s i t y space o f space straight Y end fraction?

        • 1 fifth

        • 4 over 9

        • 1

        • 5 over 2

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        7
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        According to the Bohr model for hydrogen, visible light is emitted when electrons transition to the energy state n = 2 from higher excited states. 

        The dotted line in the diagram represents a transition from n = 3 to n = 2 in the spectrum of hydrogen. 

        12-1-hl-mcq-medium-q10-diagram

        Which of the following diagrams could represent the visible light emission spectrum of hydrogen? 

        12-1-hl-mcq-medium-q10-real_options

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          The energy level diagram below shows six possible transitions between the energy levels of an atom. Each transition between levels creates a photon of definite energy and frequency.

          7-1-sl-mcq-hard-q1-phy

          The increase in frequency is from left to right.

          Which of the following spectra is the best representation of the transitions?

          7-1-sl-mcq-hard-q1_2-phy

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            2
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            Transitions between three energy levels in a particular atom give rise to the three spectral lines of frequencies, in decreasing magnitude f subscript 1, f subscript 2 and f subscript 3 with wavelengths lambda subscript 1, lambda subscript 2 and lambda subscript 3.

            Which of the following correctly relates f subscript 1, f subscript 2 and f subscript 3 and lambda subscript 1, lambda subscript 2 and lambda subscript 3. 

              Frequency Wavelength
            A. f subscript 3 space equals space f subscript 1 space plus space f subscript 2 1 over lambda subscript 1 space equals space 1 over lambda subscript 2 space plus space 1 over lambda subscript 3
            B. f subscript 3 space equals space f subscript 1 space minus space f subscript 2 1 over lambda subscript 1 space equals space 1 over lambda subscript 2 space plus space 1 over lambda subscript 3
            C. 1 over f subscript 1 space equals space 1 over f subscript 2 space minus space 1 over f subscript 3 lambda subscript 1 space equals space lambda subscript 2 space plus space lambda subscript 3
            D. 1 over f subscript 1 space equals space 1 over f subscript 2 space plus space 1 over f subscript 3 1 over lambda subscript 3 space equals space 1 over lambda subscript 1 space minus space 1 over lambda subscript 2

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              3
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              In an α–particle scattering experiment, a student set up the apparatus, as shown in the diagram below, to determine the number n of α–particles incident per unit time on a detector held at various angles θ.

              q12-1-8-1-mcq-alpha-beta-gamma-radiation

              Which of the following graphs best represents the variation of n with θ?

              q12-2-8-1-mcq-alpha-beta-gamma-radiation

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                4
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                A particular emission is indicated by the arrow on the line spectrum below.

                q25_energy-levels-_-photon-emission_aqa-as-physics-mcq

                The frequency increases from left to right. The associated energy level transitions for the these emission lines are shown below.

                ib-physics-structure-of-the-atom-h-mcq-q10

                Which transition is the line in the emission spectrum indicating?

                • E subscript 3 space rightwards arrow space E subscript 0

                • E subscript 2 space rightwards arrow space E subscript 1

                • E subscript 2 space rightwards arrow space E subscript 0

                • E subscript 4 space rightwards arrow space E subscript 1

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                5
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                The diagram shows some of the energy levels for a hydrogen atom.

                q17-energy-levels-and-photon-emission-aqa-as-physics-mcq

                A free electron of kinetic energy 12.5 eV collides with a hydrogen atom in its ground state. The hydrogen atom is excited from its ground state to the first excited state.

                The kinetic energy of the free electron after the collision is

                • 2.3 eV

                • 3.4 eV

                • 23 eV

                • 60 eV

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                6
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                In 1890 Johannes Rydberg discovered an empirical formula that enabled the wavelengths of the light in the atomic line spectrum of hydrogen to be calculated. The formula is:

                1 over lambda space equals space R subscript H open parentheses 1 over n squared minus 1 over m squared close parentheses

                Where λ is the wavelength, n and m are integers and RH is the Rydberg constant.

                In 1913 Niels Bohr published his theory of the hydrogen atom. This theory enabled the Rydberg formula to be derived. His theory also showed that the energy levels En of the hydrogen atom are given by the formula: 

                E subscript n space equals space fraction numerator 2.2 cross times 10 to the power of negative 18 end exponent over denominator n squared end fraction

                Where En is measured in joules. 

                Which of the following is a valid expression for the Rydberg constant?

                • R subscript H space equals space 2.2 cross times 10 to the power of negative 18 end exponent

                • R subscript H space equals space fraction numerator 2.2 cross times 10 to the power of negative 18 end exponent over denominator h c space open parentheses 1 minus n squared over m squared close parentheses end fraction

                • R subscript H space equals space fraction numerator 2.2 cross times 10 to the power of negative 18 end exponent over denominator h c end fraction

                • R subscript H space equals space 2.2 cross times 10 to the power of negative 18 end exponent space open parentheses fraction numerator n squared minus m squared over denominator m squared minus n squared end fraction close parentheses

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                7
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                Three statements regarding the Bohr model of the hydrogen atom are:

                I.
                The momentum of an electron is equal to the Planck constant divided by its de Broglie wavelength
                II.
                The angular momentum of the atom is quantised
                III.
                The energy levels are quantised
                 

                Which statements originate from the idea that the circumference of the orbit must be an integer number of de Broglie wavelengths?

                • I and II only

                • I and III only

                • II and III only

                • I, II and III

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                8
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                Alpha particles with various energy E are directed at a nuclei with atomic number Z. Small deviations from the predictions of the Rutherford scattering model are observed.

                Which value of E and Z is most likely to result in the greatest deviations from the Rutherford scattering model?

                  E / MeV Z
                A. 39.0 350
                B. 2.4 190
                C. 39.0 190
                D. 2.5 350

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                  9
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                  The diameter of an iridium-192 open parentheses Ir presubscript 77 presuperscript 192 close parentheses nucleus is approximately four times that of the diameter of a nucleus of which isotope?

                  • H presubscript 1 presuperscript 3

                  • T presubscript 22 presuperscript 48 i

                  • B presubscript 5 presuperscript 11

                  • L presubscript 3 presuperscript 7 i

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                  10
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                  The ratio fraction numerator r a d i u s space o f space n u c l e u s space straight Y over denominator r a d i u s space o f space n u c l e u s space straight X end fraction is equal to 1.2 where nucleus X is straight X presubscript 80 presuperscript 125 .

                  How many nucleons does nucleus Y have?

                  • 6

                  • 36

                  • 125

                  • 216

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                  11
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                  Which expression evaluates the de Broglie wavelength of an electron of mass m and charge e in the n = 2 state of hydrogen? 

                  • fraction numerator h over denominator square root of 2 m e end root end fraction

                  • fraction numerator h over denominator square root of 3.4 m e end root end fraction

                  • fraction numerator h over denominator square root of 6.8 m e end root end fraction

                  • fraction numerator h over denominator square root of 13.6 m e end root end fraction

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