ورودثبت‌نام رایگان

VSEPR Flashcards: Molecular Geometry & Bond Angles

Practice VSEPR shapes, electron geometry, lone pairs, AXE notation, and ideal bond angles with 78 focused English flashcards.

نوشتهٔ Open Study Contributor

دربارهٔ این دسته

Practice VSEPR molecular geometry with 78 English flashcards for high-school and introductory-college chemistry. You should already be able to read simple formulas and Lewis structures. This is focused shape prediction and recall, not a complete chemistry course.

Cards map electron-domain counts to electron geometry; AXE notation to molecular shape and, where lone pairs change the shape, to electron geometry; and selected molecular formulas to shape. Separate prompts retrieve ideal bond-angle benchmarks. A few reverse prompts recover AXE notation from a shape plus its domain count. Contrast and error-diagnosis questions distinguish electron geometry from molecular geometry, count multiple bonds correctly, and show why a shape name alone may not determine the domain count or an exact angle.

The 13 cases are AX₂; AX₃ and AX₂E; AX₄, AX₃E, and AX₂E₂; AX₅, AX₄E, AX₃E₂, and AX₂E₃; and AX₆, AX₅E, and AX₄E₂. Later cards cover axial and equatorial sites, usual lone-pair placements, and ideal versus actual angles. The sequence starts with domains and notation, develops two-to-four-domain cases, then interleaves five- and six-domain cases before final comparisons. Related prompts are separated; the review scheduler handles longer-term spacing.

Practice is text based. Diagram identification, exhaustive Lewis-structure construction, formal charges, polarity, radicals, transition-metal coordination, seven-domain cases, hybridization, and molecular-orbital theory are excluded to keep the deck focused. Shape-to-molecule lists and every possible reverse mapping are omitted because many answers would be valid. Numerical species-angle tables are omitted: ideal benchmarks do not give exact measured angles for every molecule.

All cards carry the VSEPR tag. Original questions, answers, organization, and metadata were prepared with AI assistance and checked against university chemistry references. The cover is an original AI-generated illustration of a generic tetrahedral model; its colors do not identify elements. No source prose, diagrams, competitor cards, or examination questions were copied. Common chemical facts are not claimed as proprietary. Original material, including the generated cover to the extent applicable rights exist, is dedicated under CC0 1.0. This is independent study material, with no university, course, or examination endorsement.

کارت‌های این دسته

  1. کارت ۱

    پرسش

    In VSEPR, what is an electron domain around a central atom?

    پاسخ

    A region of electron density: one bond to a neighboring atom, regardless of bond order, or one lone pair.

  2. کارت ۲

    پرسش

    What does the VSEPR model use to predict a central atom’s geometry?

    پاسخ

    Repulsion between electron domains. The domains favor an arrangement that reduces their mutual repulsion.

  3. کارت ۳

    پرسش

    In AXₙEₘ notation, what does A represent?

    پاسخ

    The central atom whose local geometry is being described.

  4. کارت ۴

    پرسش

    How do electron geometry and molecular geometry differ in VSEPR?

    پاسخ

    Electron geometry includes all electron domains. Molecular geometry describes the arrangement of atoms around the central atom, leaving lone pairs out of the shape name.

  5. کارت ۵

    پرسش

    How many VSEPR domains does one triple bond contribute at either bonded atom?

    پاسخ

    One domain. Three shared electron pairs occupy one bonding direction.

  6. کارت ۶

    پرسش

    In AXₙEₘ notation, what does n count?

    پاسخ

    Atoms directly bonded to the central atom. A double or triple bond still contributes one X.

  7. کارت ۷

    پرسش

    For a molecule with several central atoms, where do you apply VSEPR?

    پاسخ

    At each central atom separately, using its own bonded neighbors and lone pairs.

  8. کارت ۸

    پرسش

    In AXₙEₘ notation, what does m count?

    پاسخ

    Lone pairs on the central atom. E counts pairs, not individual electrons.

  9. کارت ۹

    پرسش

    For an AXₙEₘ center in the usual closed-shell VSEPR model, how many electron domains are present?

    پاسخ

    n + m domains: bonded neighbors plus lone pairs.

  10. کارت ۱۰

    پرسش

    VSEPR molecular shape of AX₂, with no lone pairs on A?

    پاسخ

    Linear. The two bonded atoms lie on opposite sides of the central atom.

  11. کارت ۱۱

    پرسش

    VSEPR molecular shape of AX₃, with no lone pairs on A?

    پاسخ

    Trigonal planar. The central atom and three bonded atoms lie in one plane.

  12. کارت ۱۲

    پرسش

    In an X–A–X bond angle, at which atom is the angle measured?

    پاسخ

    At A, the central atom, between the two bonds to X atoms.

  13. کارت ۱۳

    پرسش

    Does a lone pair count as one VSEPR domain or two?

    پاسخ

    One domain. The pair contains two electrons, but it occupies one region around the central atom.

  14. کارت ۱۴

    پرسش

    VSEPR molecular shape of AX₄, with no lone pairs on A?

    پاسخ

    Tetrahedral. The four bonded atoms occupy the corners of a tetrahedron around A.

  15. کارت ۱۵

    پرسش

    VSEPR molecular shape of AX₂E?

    پاسخ

    Bent, also called angular or V-shaped. There are two bonded atoms and one lone pair around A.

  16. کارت ۱۶

    پرسش

    What is the ideal X–A–X bond angle in AX₂ with no lone pairs?

    پاسخ

    180°.

  17. کارت ۱۷

    پرسش

    What electron geometry does VSEPR assign to three domains around a central atom?

    پاسخ

    Trigonal planar.

  18. کارت ۱۸

    پرسش

    VSEPR molecular shape of AX₃E?

    پاسخ

    Trigonal pyramidal. Three bonded atoms and one lone pair occupy four electron domains.

  19. کارت ۱۹

    پرسش

    What is the ideal X–A–X bond angle in tetrahedral AX₄?

    پاسخ

    About 109.5°.

  20. کارت ۲۰

    پرسش

    A central atom has two bonded neighbors and two lone pairs. What is its AXE notation?

    پاسخ

    AX₂E₂.

  21. کارت ۲۱

    پرسش

    What is the ideal X–A–X bond angle in trigonal planar AX₃?

    پاسخ

    120°.

  22. کارت ۲۲

    پرسش

    VSEPR molecular shape of AX₂E₂?

    پاسخ

    Bent, also called angular or V-shaped. Two lone pairs occupy the other two domains.

  23. کارت ۲۳

    پرسش

    What is the electron geometry around A in AX₃E?

    پاسخ

    Tetrahedral: three bonding domains plus one lone-pair domain.

  24. کارت ۲۴

    پرسش

    In O=C=O, how many electron domains surround carbon?

    پاسخ

    Two domains. Each C=O double bond counts once.

  25. کارت ۲۵

    پرسش

    What is the electron geometry around A in AX₂E?

    پاسخ

    Trigonal planar: two bonding domains plus one lone-pair domain.

  26. کارت ۲۶

    پرسش

    What molecular shape does VSEPR predict around carbon in CH₄?

    پاسخ

    Tetrahedral. Carbon has four bonded neighbors and no lone pairs.

  27. کارت ۲۷

    پرسش

    A learner counts a double bond as two VSEPR domains. What should they correct?

    پاسخ

    Count it as one domain. Bond order changes the number of shared electrons, not the number of bonded directions.

  28. کارت ۲۸

    پرسش

    What molecular shape does VSEPR predict around nitrogen in NH₃?

    پاسخ

    Trigonal pyramidal. Nitrogen has three bonded neighbors and one lone pair.

  29. کارت ۲۹

    پرسش

    What electron geometry does VSEPR assign to four domains around a central atom?

    پاسخ

    Tetrahedral.

  30. کارت ۳۰

    پرسش

    What molecular shape does VSEPR predict around oxygen in H₂O?

    پاسخ

    Bent. Oxygen has two bonded neighbors and two lone pairs.

  31. کارت ۳۱

    پرسش

    What molecular shape does VSEPR predict around carbon in the carbonate ion, CO₃²⁻?

    پاسخ

    Trigonal planar. The three C–O bonding directions give three domains, even when a Lewis structure shows one double bond.

  32. کارت ۳۲

    پرسش

    In the simple VSEPR model, how does a central lone pair usually affect neighboring bond angles?

    پاسخ

    It tends to compress nearby bond angles because its electron density occupies more space near the central atom. This is a qualitative tendency, not a fixed number of degrees.

  33. کارت ۳۳

    پرسش

    A VSEPR center is trigonal pyramidal with four total domains. What is its AXE notation?

    پاسخ

    AX₃E: three bonded atoms and one lone pair.

  34. کارت ۳۴

    پرسش

    Which two common AXE cases give a bent molecular shape with three or four total domains?

    پاسخ

    AX₂E with three domains, and AX₂E₂ with four domains. Their electron geometries differ.

  35. کارت ۳۵

    پرسش

    What electron geometry does VSEPR assign to five domains around a central atom?

    پاسخ

    Trigonal bipyramidal.

  36. کارت ۳۶

    پرسش

    What electron geometry does VSEPR assign to six domains around a central atom?

    پاسخ

    Octahedral.

  37. کارت ۳۷

    پرسش

    Does an ideal VSEPR angle give the exact measured angle in every molecule of that shape?

    پاسخ

    No. It is a geometric benchmark; lone pairs and the bonding environment can change actual angles.

  38. کارت ۳۸

    پرسش

    How many axial and equatorial positions are in a trigonal bipyramid?

    پاسخ

    Two axial positions and three equatorial positions.

  39. کارت ۳۹

    پرسش

    VSEPR molecular shape of AX₅, with no lone pairs on A?

    پاسخ

    Trigonal bipyramidal.

  40. کارت ۴۰

    پرسش

    VSEPR molecular shape of AX₆, with no lone pairs on A?

    پاسخ

    Octahedral.

  41. کارت ۴۱

    پرسش

    VSEPR molecular shape of AX₄E in the usual lowest-repulsion arrangement?

    پاسخ

    Seesaw. The lone pair occupies an equatorial position in a trigonal-bipyramidal domain arrangement.

  42. کارت ۴۲

    پرسش

    In an ideal trigonal bipyramid, what is the angle between two equatorial bonds?

    پاسخ

    120°.

  43. کارت ۴۳

    پرسش

    VSEPR molecular shape of AX₃E₂ in the usual lowest-repulsion arrangement?

    پاسخ

    T-shaped. Both lone pairs occupy equatorial positions.

  44. کارت ۴۴

    پرسش

    VSEPR molecular shape of AX₅E?

    پاسخ

    Square pyramidal. One lone pair occupies the sixth position of an octahedral domain arrangement.

  45. کارت ۴۵

    پرسش

    In an ideal trigonal bipyramid, what is the angle between an axial bond and an equatorial bond?

    پاسخ

    90°.

  46. کارت ۴۶

    پرسش

    VSEPR molecular shape of AX₂E₃ in the usual lowest-repulsion arrangement?

    پاسخ

    Linear. Three equatorial lone pairs leave the two bonded atoms in opposite axial positions.

  47. کارت ۴۷

    پرسش

    VSEPR molecular shape of AX₄E₂ in the usual lowest-repulsion arrangement?

    پاسخ

    Square planar. Two opposite lone pairs leave four bonded atoms in a square around A.

  48. کارت ۴۸

    پرسش

    In a trigonal-bipyramidal domain arrangement, which sites do lone pairs preferentially occupy?

    پاسخ

    Equatorial sites, in the usual VSEPR arrangements with one to three lone pairs.

  49. کارت ۴۹

    پرسش

    Which X–A–X angles occur in an ideal octahedral AX₆ molecule?

    پاسخ

    90° between adjacent bonds and 180° between opposite bonds.

  50. کارت ۵۰

    پرسش

    A VSEPR center has a seesaw shape and five total domains. What is its AXE notation?

    پاسخ

    AX₄E.

  51. کارت ۵۱

    پرسش

    A VSEPR center has a T-shaped molecular geometry and five total domains. What is its AXE notation?

    پاسخ

    AX₃E₂.

  52. کارت ۵۲

    پرسش

    In an ideal trigonal bipyramid, what is the angle between its two axial bonds?

    پاسخ

    180°. The axial positions lie on opposite sides of the central atom.

  53. کارت ۵۳

    پرسش

    A VSEPR center is square pyramidal with six total domains. What is its AXE notation?

    پاسخ

    AX₅E.

  54. کارت ۵۴

    پرسش

    In the usual octahedral AX₄E₂ arrangement, how are the two lone pairs positioned relative to each other?

    پاسخ

    Opposite each other, 180° apart in the ideal domain arrangement.

  55. کارت ۵۵

    پرسش

    What molecular shape does VSEPR predict for an isolated SF₄ molecule?

    پاسخ

    Seesaw. Sulfur has four bonded fluorine atoms and one lone pair.

  56. کارت ۵۶

    پرسش

    What molecular shape does VSEPR predict for an isolated XeF₂ molecule?

    پاسخ

    Linear. Xenon has two bonded fluorine atoms and three lone pairs.

  57. کارت ۵۷

    پرسش

    What is the electron geometry around A in AX₃E₂?

    پاسخ

    Trigonal bipyramidal: three bonding domains plus two lone-pair domains.

  58. کارت ۵۸

    پرسش

    What molecular shape does VSEPR predict for an isolated BrF₅ molecule?

    پاسخ

    Square pyramidal. Bromine has five bonded fluorine atoms and one lone pair.

  59. کارت ۵۹

    پرسش

    What molecular shape does VSEPR predict for an isolated XeF₄ molecule?

    پاسخ

    Square planar. Xenon has four bonded fluorine atoms and two opposite lone pairs.

  60. کارت ۶۰

    پرسش

    What is the electron geometry around A in AX₄E?

    پاسخ

    Trigonal bipyramidal: four bonding domains plus one lone-pair domain.

  61. کارت ۶۱

    پرسش

    What molecular shape does VSEPR predict for an isolated ClF₃ molecule?

    پاسخ

    T-shaped. Chlorine has three bonded fluorine atoms and two equatorial lone pairs.

  62. کارت ۶۲

    پرسش

    What is the electron geometry around A in AX₅E?

    پاسخ

    Octahedral: five bonding domains plus one lone-pair domain.

  63. کارت ۶۳

    پرسش

    What is the electron geometry around A in AX₂E₃?

    پاسخ

    Trigonal bipyramidal: two bonding domains plus three lone-pair domains.

  64. کارت ۶۴

    پرسش

    What molecular shape does VSEPR predict for an isolated SF₆ molecule?

    پاسخ

    Octahedral. Sulfur has six bonded fluorine atoms and no lone pairs.

  65. کارت ۶۵

    پرسش

    Which bond angles occur in an idealized T-shaped AX₃E₂ arrangement?

    پاسخ

    90° and 180°. These are parent-geometry benchmarks; a real molecule can be distorted.

  66. کارت ۶۶

    پرسش

    What is the electron geometry around A in AX₄E₂?

    پاسخ

    Octahedral: four bonding domains plus two lone-pair domains.

  67. کارت ۶۷

    پرسش

    Why does an octahedral VSEPR arrangement have six domains despite the name’s reference to eight?

    پاسخ

    The six domains point toward the six vertices of an octahedron. Eight refers to the solid’s faces.

  68. کارت ۶۸

    پرسش

    Why does a lone pair in AX₄E favor an equatorial site over an axial site?

    پاسخ

    An equatorial site has two 90° interactions with other domains; an axial site has three. The equatorial choice reduces these close repulsions.

  69. کارت ۶۹

    پرسش

    Which common AXE cases give a linear molecular shape with two or five total domains?

    پاسخ

    AX₂ with two domains, and AX₂E₃ with five domains. A linear shape alone does not determine the electron geometry.

  70. کارت ۷۰

    پرسش

    Which bond angles occur in an idealized square-pyramidal AX₅E arrangement?

    پاسخ

    90° and 180°. Actual angles can deviate from these octahedral parent benchmarks.

  71. کارت ۷۱

    پرسش

    A VSEPR center is square planar with six total domains. What is its AXE notation?

    پاسخ

    AX₄E₂.

  72. کارت ۷۲

    پرسش

    A learner assigns every bent molecule the same bond angle. What information are they missing?

    پاسخ

    The electron-domain arrangement and the particular molecule. Bent includes AX₂E and AX₂E₂, and actual angles depend on the species.

  73. کارت ۷۳

    پرسش

    A learner calls NH₃ tetrahedral because nitrogen has four domains. What shape distinction resolves the error?

    پاسخ

    Tetrahedral is its electron geometry. Its molecular geometry is trigonal pyramidal because only the three bonded atoms define that shape.

  74. کارت ۷۴

    پرسش

    Why can four bonded atoms give tetrahedral AX₄ but square planar AX₄E₂?

    پاسخ

    AX₄ has four total domains. AX₄E₂ has six total domains, with two opposite lone pairs in an octahedral arrangement.

  75. کارت ۷۵

    پرسش

    Which ideal parent angles are the benchmarks for an AX₄E seesaw arrangement?

    پاسخ

    90°, 120°, and 180° from trigonal-bipyramidal electron geometry. Lone-pair repulsion can distort the actual bond angles.

  76. کارت ۷۶

    پرسش

    What molecular shape does VSEPR predict for an isolated PF₅ molecule?

    پاسخ

    Trigonal bipyramidal. Phosphorus has five bonded fluorine atoms and no lone pairs.

  77. کارت ۷۷

    پرسش

    What is the electron geometry around A in AX₂E₂?

    پاسخ

    Tetrahedral: two bonding domains plus two lone-pair domains.

  78. کارت ۷۸

    پرسش

    Which X–A–X bond angles occur in an ideal square-planar AX₄E₂ arrangement?

    پاسخ

    90° between adjacent bonds and 180° between opposite bonds.

A generic tetrahedral ball-and-stick model with an orange center and four teal neighbors against a dark blue background.

۷۸ کارت

VSEPR Flashcards: Molecular Geometry & Bond Angles

این دسته را رایگان مطالعه کنید

Nibomo باز می‌شود تا بتوانید مطالعه را شروع کنید.