Q1 · June 2021 · 2 marks
Plutonium (atomic mass = 244 \mathrm{g\,mol^{-1}}) crystallizes in monoclinic lattice (a = 620 pm, b = 480 pm, c = 1100 pm; \beta = 102°) with 16 atoms per unit cell. The density in \mathrm{g\,cm^{-3}} will be close to (Use \sin\beta = 0.98; \sin\beta/2 = 0.78)
- (b) 16.12
- (a) 25.38
- (c) 12.69
- (d) 20.26
Show answer
Answer: (d)
Report an error in ABC26PH1366
Q2 · 2019 · 2 marks
Nearest neighbour distance in a crystal system of side length a is \frac{a}{\sqrt{2}} in
- (a) Face-centered cube
- (b) Body-centered cube
- (c) Trigonal primitive
- (d) Primitive cube
Show answer
Answer: (a)
Report an error in ABC26PH1361
Q3 · Dec 2019 · 2 marks
The Miller index for the plane as shown in the figure and parallel to the c-axis, is 
- (a) 110
- (b) 120
- (c) 210
- (d) 220
Show answer
Answer: (b)
Report an error in ABC26PH1362
Q4 · Dec 2019 · 2 marks
X-rays of 173 pm wavelength are reflected by the (111) plane of a cubic primitive crystal at \theta = 30°. The unit cell length (in pm) is closest to
- (a) 173
- (b) 300
- (c) 346
- (d) 600
Show answer
Answer: (b)
Report an error in ABC26PH1363
Q5 · Dec 2019 · 2 marks
Iron belongs to the BCC lattice. The Miller indices of the second allowed reflection in the powder diffraction pattern of iron would be
- (a) (100)
- (b) (111)
- (c) (200)
- (d) (210)
Show answer
Answer: (c)
Report an error in ABC26PH1364
Q6 · Dec 2019 · 2 marks
In the ccp packing, the number of lattice points per unit area in the planes is in the order
- (a) (100) > (110) > (111)
- (b) (100) > (111) > (110)
- (c) (111) > (100) > (110)
- (d) (111) > (110) > (100)
Show answer
Answer: (c)
Report an error in ABC26PH1365
Q7 · Dec 2017 · 2 marks
If all the lattice points of an FCC structure are occupied by uniform hard spheres that touch each other, the fraction of volume occupied is
- (a) \frac{\pi \sqrt{2}}{6}
- (b) \frac{\pi \sqrt{3}}{6}
- (c) \frac{\pi}{6}
- (d) \frac{2 \pi}{6}
Show answer
Answer: (a)
Report an error in ABC26PH1356
Q8 · Dec 2017 · 2 marks
The (002) plane of an elemental FCC crystal diffracts X-rays ( \lambda=0.154 \mathrm{~nm} ) at Bragg angle 90^{\circ}. the density of the crystal is 4 \times 10^{4} \mathrm{~kg} \mathrm{~m}^{-3}. The atomic weight of the elemental solid is
- (a) 22
- (b) 44
- (c) 88
- (d) 66
Show answer
Answer: (a)
Report an error in ABC26PH1357
Q9 · Dec 2018 · 2 marks
In a cubic crystal, the (111) and (222) reflections are observed, but not the (001) reflection. The Bravais lattice is
- (a) body centred cubic
- (b) face centred cubic
- (c) simple cubic
- (d) side centred cubic
Show answer
Answer: (b)
Report an error in ABC26PH1358
Q10 · Dec 2018 · 2 marks
A metal crystallizes with cubic close-packed structure. The \sin^2\theta values of Bragg reflections of Miller Planes (200) and (111) are 0.18 and 0.14, respectively. The unit cell length is
- (a) \lambda/2
- (b) \lambda/0.3
- (c) \lambda/0.4
- (d) 0.4\lambda
Show answer
Answer: (a)
Report an error in ABC26PH1359
Q11 · June 2017 · 2 marks
Metallic silver crystallizes in face-centred-cubic lattice structure with a unit cell of length 40 nm. The first order diffraction angle of X-ray beam from (2, 1, 0) plane of silver is 30°. The wavelength of X-ray used is close to
- (a) 11 nm
- (b) 18 nm
- (c) 25 nm
- (d) 32 nm
Show answer
Answer: (b)
Report an error in ABC26PH1352
Q12 · June 2017 · 2 marks
Polonium is the only metal known to exist in a simple cubic lattice form. The density of polonium at 0°C is measured to be 10.00\ \mathrm{g/cm^3}. The atomic radius of polonium would then be (assume the mass of a polonium atom = 2.7 \times 10^{-22} g)
- (a) 1.1 Å
- (b) 1.9 Å
- (c) 1.5 Å
- (d) 2.3 Å
Show answer
Answer: (c)
Report an error in ABC26PH1353
Q13 · Dec 2017 · 2 marks
The separation of the (123) planes of an orthorhombic unit cell is 3.12 nm . The separation of (246) and (369) planes are, respectively,
- (a) 1.56 nm and 1.04 nm
- (b) 1.04 nm and 1.56 nm
- (c) 3.12 m and 1.50 nm
- (d) 1.04 nm and 3.12 nm
Show answer
Answer: (a)
Report an error in ABC26PH1355
Q14 · June 2016 · 2 marks
In a cubic crystal, the plane [100] is equally inclined to the planes
- (a) [010] and [011]
- (b) [010] and [110]
- (c) [001] and [101]
- (d) [110] and [011]
Show answer
Answer: (a)
Report an error in ABC26PH1348
Q15 · Dec 2016 · 2 marks
Each void in a two dimensional hexagonal close-packed layer of circles is surrounded by
- (a) six circles
- (b) three circles
- (c) four circles
- (d) twelve circles
Show answer
Answer: (b)
Report an error in ABC26PH1350
Q16 · Dec 2016 · 2 marks
The \sin ^{2} \theta values obtained from X -ray powder diffraction pattern of a solid are 2 \mathrm{x}, 4 \mathrm{x}, 6 x, 8 x where x is equal to 0.06 . The wavelength of X-ray used to obtain this pattern is 1.54 \AA. The unit cell and the unit cell length, respectively are
- (a) \mathbf{B C C}, \mathbf{3 . 1 4 6} \AA
- (b) \mathbf{F C C}, \mathbf{3 . 1 4 6} \boldsymbol{\AA}
- (c) SCC, 6.281 Å
- (d) BCC, 1.544 \AA
Show answer
Answer: (a)
Report an error in ABC26PH1351
Q17 · Dec 2015 · 2 marks
For a simple cubic crystal lattice, the angle between the [2 0 1] plane and the xy plane is
- (a) less than 30°
- (b) between 30° and 45°
- (c) between 45° and 60°
- (d) greater than 60°
Show answer
Answer: (d)
Report an error in ABC26PH1346
Q18 · Dec 2015 · 2 marks
For a simple cubic crystal, X-ray diffraction shows intense reflections for angles \theta_{1} and \theta_{2} which are assigned to [ 10 1] and [ 11 1] planes, resectively. The ratio \sin \theta_{1} / \sin \theta_{2} is
- (a) 1.5
- (b) 1.22
- (c) 0.82
- (d) 0.67
Show answer
Answer: (c)
Report an error in ABC26PH1347
Q19 · June 2014 · 2 marks
A compound A_{x} B_{y} has a cubic structure with A atoms occupying all the corners of the cube as well as all the face center positions. The \mathbf{B} atoms occupy four tetrahedral voids. The values of x and y respectively, are
- (a) 4,4
- (b) 4,8
- (c) 8,4
- (d) 4,2
Show answer
Answer: (a)
Report an error in ABC26PH1342
Q20 · Dec 2014 · 2 marks
X-ray diffraction does not give any structural information for
- (a) metallic solids
- (b) ionic solids
- (c) molecular solids
- (d) amorphous solids X-ray diffraction give any structural information only for crystalline solids
Show answer
Answer: (d)
Report an error in ABC26PH1343
Q21 · Dec 2014 · 2 marks
A solid consisting of only X-atoms has a close-packed structure with X-X distance of 160 pm. Assuming it to be a closed packed structure of hard spheres with radius equal to half of the X-X bond length, the number of atoms in 1\ \mathrm{cm^3} would be
- (a) 6.023 \times 10^{27}
- (b) 3.45 \times 10^{23}
- (c) 6.02 \times 10^{21}
- (d) 3.8 \times 10^{21}
Show answer
Answer: (b)
Report an error in ABC26PH1344
Q22 · June 2013 · 2 marks
The coordinates for the atoms in a body centred cubic unit cell are
- (a) (0, 0, 0) and (1/2, 0, 0)
- (b) (0, 0, 0) and (1/2, 1/2, 1/2)
- (c) (0, 0, 0) and (0, 1/2, 0)
- (d) (0,0,0) and (0,0,1 / 2)
Show answer
Answer: (c)
Report an error in ABC26PH1331
Q23 · June 2013 · 2 marks
The inter planar distance (Å) for a (100) plane in a cubic structure with the lattice parameter of 4 Å is:
Show answer
Answer: (c)
Report an error in ABC26PH1332
Q24 · June 2013 · 2 marks
A plane of spacing 'd' shows first order Bragg diffraction at angle \theta. A plane of spacing 2d
- (a) shows Bragg diffraction at 2\theta
- (b) shows Bragg diffraction at \theta/2
- (c) shows Bragg diffraction at \sin^{-1}(\sin\theta/2)
- (d) shows Bragg diffraction at \sin^{-1}(\sin 2\theta/2)
Show answer
Answer: (c)
Report an error in ABC26PH1333
Q25 · Dec 2013 · 2 marks
When Frenkel defects are created in an otherwise perfect ionic crystal, the density of the ionic crystal
- (a) increases
- (b) decreases
- (c) remains same
- (d) oscillates with the number of defects
Show answer
Answer: (c)
Report an error in ABC26PH1334
Q26 · Dec 2013 · 2 marks
A compound of M and X atoms has a cubic unit cell. M atoms are at the corners and body centre position and X atoms are at face centre positions of the cube. The molecular formula of the compound is
- (a) MX
- (b) \mathbf{M X}_{\mathbf{2}}
- (c) \mathbf{M}_{\mathbf{3}} \mathbf{X}_{\mathbf{2}}
- (d) \mathrm{M}_{2} \mathrm{X}_{3}
Show answer
Answer: (d)
Report an error in ABC26PH1335
Q27 · Dec 2013 · 2 marks
The angle at which the first order Bragg reflection is observed from (110) plane in a simple cubic unit cell of side 3.238 \AA, when chromium K radiation of wavelength 2.29 \AA is used, is
- (a) 30°
- (b) 45°
- (c) 60°
- (d) 90^{\circ}
Show answer
Answer: (a)
Report an error in ABC26PH1336
Q28 · Dec 2013 · 2 marks
Metallic gold crystallizes in fcc structure with unit cell dimension of 4.00 Å. The atomic radius of gold is
- (a) 0.866 Å
- (b) 1.414 Å
- (c) 1.732 Å
- (d) 2.000 Å
Show answer
Answer: (b)
Report an error in ABC26PH1339
Q29 · 2012 · 2 marks
How many atoms are there in an element packed in a fcc structure
Show answer
Answer: (c)
Report an error in ABC26PH1323
Q30 · 2012 · 2 marks
A metal crystallizes in fcc structure with a unit cell side of 500 pm . If the density of the crystal is \mathbf{1 . 3 3 ~ g} / \mathbf{c c}, the molar mass of the metal is close to
- (a) 23
- (b) 24
- (c) 25
- (d) 26
Show answer
Answer: (c)
Report an error in ABC26PH1328
Q31 · 2012 · 2 marks
The packing fraction of a simple cubic lattice is close to
- (a) 0.94
- (b) 0.76
- (c) 0.52
- (d) 0.45
Show answer
Answer: (c)
Report an error in ABC26PH1329
Q32 · 2012 · 2 marks
Crystal A diffracts from (111) and (200) planes but not from (110) plane, while the crystal B diffracts from (110) and (200) planes but not from the (111) plane. From the above, we may conclude that
- (a) A has fcc lattice while B has bcc lattice
- (b) A has bcc lattice while B has fee lattice
- (c) A and B both have fcc lattice
- (d) A and B both have bcc lattice.
Show answer
Answer: (a)
Report an error in ABC26PH1330
Q33 · 2011 · 2 marks
A one-dimensional crystal of lattice dimension 'a' is metallic. If the structure is distorted in such a way that the lattice dimension is enhanced to '2a'.
- (a) The electronic structure remains unchanged.
- (b) The width of conduction band decreases and a band gap is generated.
- (c) The width of conduction band increases
- (d) The width of the conduction band remains unchanged
Show answer
Answer: (b)
Report an error in ABC26PH1320
Q34 · 2011 · 2 marks
The value of d_{111} in a cubic crystal is 325.6 pm. The value of d_{333} is
- (a) 325.6 pm
- (b) 976.8 pm
- (c) 108.5 pm
- (d) 625.6 pm
Show answer
Answer: (b)
Report an error in ABC26PH1321
Q35 · Dec 2011 · 2 marks
Consider a n-type semiconductor whose E_V = 0, E_C = 2.0 eV and E_D = 1.98 eV. The correct statement among the following is
- (a) E_F = 1 eV and is independent of T
- (b) E_F = 1.99 eV and remains independent of T
- (c) E_F = 1.99 eV and increases towards 2.0 eV with increase of T
- (d) E_F = 1.99 eV and decreases with increase of T.
Show answer
Answer: (d)
Report an error in ABC26PH1322
ABC Chemistry
CSIR NETChemical Science Coaching
GATEChemical Science Preparation
IIT JAMM.Sc Entrance Coaching
CUET PGPost Graduate Entrance
Class 11 ChemistryLive online
Class 12 ChemistryLive onlineStudy LibraryPrevious year papers171 official papers · JAM, NET, GATE, CUETTopic-wise decks32 PDF + PPTX decks, freeBuild your own PDFChoose exam → topic → downloadStudy materialUnit-wise notes for the batchesTest papers 8–12School practice papersDreamer's QuizWeekly chemistry quizQuestions by topicRead online with verified answersSearchTopics, courses and articlesExam guidesSyllabus, pattern, eligibilityBlogChapter notes and PYQ analysisBooks by ABPeriodic table and data bookGreat Home TutorPh.DAboutContactBlogsQ&A▶️ YouTubeEnquiryBook a free demoCall +91 92121 42427