Virtual Labs

Determination of Precise Lattice Parameter of FCC and BCC phases using X-Rays diffraction

1) Which factor most strongly affects the precision of lattice parameter determination in XRD?

a: Sample thickness Explanation

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b: Peak position accuracy Explanation

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c: Peak intensity Explanation

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d: Background noise Explanation

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2) The use of high-angle diffraction peaks improves lattice parameter accuracy primarily because:

a: They have higher intensity Explanation

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b: Instrumental broadening is reduced Explanation

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c: Δd/d decreases with increasing θ Explanation

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d: absorption effects are minimized Explanation

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3) Which systematic error causes a uniform shift in all diffraction peaks?

a: Preferred orientation Explanation

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b: Zero shift error Explanation

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c: Crystallite size effect Explanation

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d: Microstrain Explanation

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4) The Nelson–Riley function is used to:

a: Correct peak broadening Explanation

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b: Separate strain and size effects Explanation

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c: Extrapolate lattice parameters to θ = 90° Explanation

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d: Index unknown diffraction peaks Explanation

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5) What does the '2θ' value in an XRD plot represent?

a: The angle of incident X-rays Explanation

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b: The angle between the incident and diffracted X-rays Explanation

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c: The atomic number of the elements in the sample Explanation

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d: The temperature at which the sample is analysed Explanation

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6) A diffraction peak is observed at 2θ=44.5∘ using Cu-Kα radiation (λ=1.5406 Å). What is the corresponding interplanar spacing d?

a: 1.54 Å Explanation

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b: 2.03 Å Explanation

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c: 2.50 Å Explanation

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d: 3.12 Å Explanation

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7) The d-spacing corresponding to the (110) plane of a BCC crystal is 2.03 Å. The lattice parameter is:

a: 2.03 Å Explanation

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b: 2.87 Å Explanation

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c: 3.52 Å Explanation

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d: 4.06 Å Explanation

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