VSEPR Flashcards: Molecular Geometry & Bond Angles
Practice VSEPR shapes, electron geometry, lone pairs, AXE notation, and ideal bond angles with 78 focused English flashcards.
Despre acest pachet
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.
Fișele din acest pachet
Fișa 1
Întrebare
In VSEPR, what is an electron domain around a central atom?
Răspuns
A region of electron density: one bond to a neighboring atom, regardless of bond order, or one lone pair.
Fișa 2
Întrebare
What does the VSEPR model use to predict a central atom’s geometry?
Răspuns
Repulsion between electron domains. The domains favor an arrangement that reduces their mutual repulsion.
Fișa 3
Întrebare
In AXₙEₘ notation, what does A represent?
Răspuns
The central atom whose local geometry is being described.
Fișa 4
Întrebare
How do electron geometry and molecular geometry differ in VSEPR?
Răspuns
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.
Fișa 5
Întrebare
How many VSEPR domains does one triple bond contribute at either bonded atom?
Răspuns
One domain. Three shared electron pairs occupy one bonding direction.
Fișa 6
Întrebare
In AXₙEₘ notation, what does n count?
Răspuns
Atoms directly bonded to the central atom. A double or triple bond still contributes one X.
Fișa 7
Întrebare
For a molecule with several central atoms, where do you apply VSEPR?
Răspuns
At each central atom separately, using its own bonded neighbors and lone pairs.
Fișa 8
Întrebare
In AXₙEₘ notation, what does m count?
Răspuns
Lone pairs on the central atom. E counts pairs, not individual electrons.
Fișa 9
Întrebare
For an AXₙEₘ center in the usual closed-shell VSEPR model, how many electron domains are present?
Răspuns
n + m domains: bonded neighbors plus lone pairs.
Fișa 10
Întrebare
VSEPR molecular shape of AX₂, with no lone pairs on A?
Răspuns
Linear. The two bonded atoms lie on opposite sides of the central atom.
Fișa 11
Întrebare
VSEPR molecular shape of AX₃, with no lone pairs on A?
Răspuns
Trigonal planar. The central atom and three bonded atoms lie in one plane.
Fișa 12
Întrebare
In an X–A–X bond angle, at which atom is the angle measured?
Răspuns
At A, the central atom, between the two bonds to X atoms.
Fișa 13
Întrebare
Does a lone pair count as one VSEPR domain or two?
Răspuns
One domain. The pair contains two electrons, but it occupies one region around the central atom.
Fișa 14
Întrebare
VSEPR molecular shape of AX₄, with no lone pairs on A?
Răspuns
Tetrahedral. The four bonded atoms occupy the corners of a tetrahedron around A.
Fișa 15
Întrebare
VSEPR molecular shape of AX₂E?
Răspuns
Bent, also called angular or V-shaped. There are two bonded atoms and one lone pair around A.
Fișa 16
Întrebare
What is the ideal X–A–X bond angle in AX₂ with no lone pairs?
Răspuns
180°.
Fișa 17
Întrebare
What electron geometry does VSEPR assign to three domains around a central atom?
Răspuns
Trigonal planar.
Fișa 18
Întrebare
VSEPR molecular shape of AX₃E?
Răspuns
Trigonal pyramidal. Three bonded atoms and one lone pair occupy four electron domains.
Fișa 19
Întrebare
What is the ideal X–A–X bond angle in tetrahedral AX₄?
Răspuns
About 109.5°.
Fișa 20
Întrebare
A central atom has two bonded neighbors and two lone pairs. What is its AXE notation?
Răspuns
AX₂E₂.
Fișa 21
Întrebare
What is the ideal X–A–X bond angle in trigonal planar AX₃?
Răspuns
120°.
Fișa 22
Întrebare
VSEPR molecular shape of AX₂E₂?
Răspuns
Bent, also called angular or V-shaped. Two lone pairs occupy the other two domains.
Fișa 23
Întrebare
What is the electron geometry around A in AX₃E?
Răspuns
Tetrahedral: three bonding domains plus one lone-pair domain.
Fișa 24
Întrebare
In O=C=O, how many electron domains surround carbon?
Răspuns
Two domains. Each C=O double bond counts once.
Fișa 25
Întrebare
What is the electron geometry around A in AX₂E?
Răspuns
Trigonal planar: two bonding domains plus one lone-pair domain.
Fișa 26
Întrebare
What molecular shape does VSEPR predict around carbon in CH₄?
Răspuns
Tetrahedral. Carbon has four bonded neighbors and no lone pairs.
Fișa 27
Întrebare
A learner counts a double bond as two VSEPR domains. What should they correct?
Răspuns
Count it as one domain. Bond order changes the number of shared electrons, not the number of bonded directions.
Fișa 28
Întrebare
What molecular shape does VSEPR predict around nitrogen in NH₃?
Răspuns
Trigonal pyramidal. Nitrogen has three bonded neighbors and one lone pair.
Fișa 29
Întrebare
What electron geometry does VSEPR assign to four domains around a central atom?
Răspuns
Tetrahedral.
Fișa 30
Întrebare
What molecular shape does VSEPR predict around oxygen in H₂O?
Răspuns
Bent. Oxygen has two bonded neighbors and two lone pairs.
Fișa 31
Întrebare
What molecular shape does VSEPR predict around carbon in the carbonate ion, CO₃²⁻?
Răspuns
Trigonal planar. The three C–O bonding directions give three domains, even when a Lewis structure shows one double bond.
Fișa 32
Întrebare
In the simple VSEPR model, how does a central lone pair usually affect neighboring bond angles?
Răspuns
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.
Fișa 33
Întrebare
A VSEPR center is trigonal pyramidal with four total domains. What is its AXE notation?
Răspuns
AX₃E: three bonded atoms and one lone pair.
Fișa 34
Întrebare
Which two common AXE cases give a bent molecular shape with three or four total domains?
Răspuns
AX₂E with three domains, and AX₂E₂ with four domains. Their electron geometries differ.
Fișa 35
Întrebare
What electron geometry does VSEPR assign to five domains around a central atom?
Răspuns
Trigonal bipyramidal.
Fișa 36
Întrebare
What electron geometry does VSEPR assign to six domains around a central atom?
Răspuns
Octahedral.
Fișa 37
Întrebare
Does an ideal VSEPR angle give the exact measured angle in every molecule of that shape?
Răspuns
No. It is a geometric benchmark; lone pairs and the bonding environment can change actual angles.
Fișa 38
Întrebare
How many axial and equatorial positions are in a trigonal bipyramid?
Răspuns
Two axial positions and three equatorial positions.
Fișa 39
Întrebare
VSEPR molecular shape of AX₅, with no lone pairs on A?
Răspuns
Trigonal bipyramidal.
Fișa 40
Întrebare
VSEPR molecular shape of AX₆, with no lone pairs on A?
Răspuns
Octahedral.
Fișa 41
Întrebare
VSEPR molecular shape of AX₄E in the usual lowest-repulsion arrangement?
Răspuns
Seesaw. The lone pair occupies an equatorial position in a trigonal-bipyramidal domain arrangement.
Fișa 42
Întrebare
In an ideal trigonal bipyramid, what is the angle between two equatorial bonds?
Răspuns
120°.
Fișa 43
Întrebare
VSEPR molecular shape of AX₃E₂ in the usual lowest-repulsion arrangement?
Răspuns
T-shaped. Both lone pairs occupy equatorial positions.
Fișa 44
Întrebare
VSEPR molecular shape of AX₅E?
Răspuns
Square pyramidal. One lone pair occupies the sixth position of an octahedral domain arrangement.
Fișa 45
Întrebare
In an ideal trigonal bipyramid, what is the angle between an axial bond and an equatorial bond?
Răspuns
90°.
Fișa 46
Întrebare
VSEPR molecular shape of AX₂E₃ in the usual lowest-repulsion arrangement?
Răspuns
Linear. Three equatorial lone pairs leave the two bonded atoms in opposite axial positions.
Fișa 47
Întrebare
VSEPR molecular shape of AX₄E₂ in the usual lowest-repulsion arrangement?
Răspuns
Square planar. Two opposite lone pairs leave four bonded atoms in a square around A.
Fișa 48
Întrebare
In a trigonal-bipyramidal domain arrangement, which sites do lone pairs preferentially occupy?
Răspuns
Equatorial sites, in the usual VSEPR arrangements with one to three lone pairs.
Fișa 49
Întrebare
Which X–A–X angles occur in an ideal octahedral AX₆ molecule?
Răspuns
90° between adjacent bonds and 180° between opposite bonds.
Fișa 50
Întrebare
A VSEPR center has a seesaw shape and five total domains. What is its AXE notation?
Răspuns
AX₄E.
Fișa 51
Întrebare
A VSEPR center has a T-shaped molecular geometry and five total domains. What is its AXE notation?
Răspuns
AX₃E₂.
Fișa 52
Întrebare
In an ideal trigonal bipyramid, what is the angle between its two axial bonds?
Răspuns
180°. The axial positions lie on opposite sides of the central atom.
Fișa 53
Întrebare
A VSEPR center is square pyramidal with six total domains. What is its AXE notation?
Răspuns
AX₅E.
Fișa 54
Întrebare
In the usual octahedral AX₄E₂ arrangement, how are the two lone pairs positioned relative to each other?
Răspuns
Opposite each other, 180° apart in the ideal domain arrangement.
Fișa 55
Întrebare
What molecular shape does VSEPR predict for an isolated SF₄ molecule?
Răspuns
Seesaw. Sulfur has four bonded fluorine atoms and one lone pair.
Fișa 56
Întrebare
What molecular shape does VSEPR predict for an isolated XeF₂ molecule?
Răspuns
Linear. Xenon has two bonded fluorine atoms and three lone pairs.
Fișa 57
Întrebare
What is the electron geometry around A in AX₃E₂?
Răspuns
Trigonal bipyramidal: three bonding domains plus two lone-pair domains.
Fișa 58
Întrebare
What molecular shape does VSEPR predict for an isolated BrF₅ molecule?
Răspuns
Square pyramidal. Bromine has five bonded fluorine atoms and one lone pair.
Fișa 59
Întrebare
What molecular shape does VSEPR predict for an isolated XeF₄ molecule?
Răspuns
Square planar. Xenon has four bonded fluorine atoms and two opposite lone pairs.
Fișa 60
Întrebare
What is the electron geometry around A in AX₄E?
Răspuns
Trigonal bipyramidal: four bonding domains plus one lone-pair domain.
Fișa 61
Întrebare
What molecular shape does VSEPR predict for an isolated ClF₃ molecule?
Răspuns
T-shaped. Chlorine has three bonded fluorine atoms and two equatorial lone pairs.
Fișa 62
Întrebare
What is the electron geometry around A in AX₅E?
Răspuns
Octahedral: five bonding domains plus one lone-pair domain.
Fișa 63
Întrebare
What is the electron geometry around A in AX₂E₃?
Răspuns
Trigonal bipyramidal: two bonding domains plus three lone-pair domains.
Fișa 64
Întrebare
What molecular shape does VSEPR predict for an isolated SF₆ molecule?
Răspuns
Octahedral. Sulfur has six bonded fluorine atoms and no lone pairs.
Fișa 65
Întrebare
Which bond angles occur in an idealized T-shaped AX₃E₂ arrangement?
Răspuns
90° and 180°. These are parent-geometry benchmarks; a real molecule can be distorted.
Fișa 66
Întrebare
What is the electron geometry around A in AX₄E₂?
Răspuns
Octahedral: four bonding domains plus two lone-pair domains.
Fișa 67
Întrebare
Why does an octahedral VSEPR arrangement have six domains despite the name’s reference to eight?
Răspuns
The six domains point toward the six vertices of an octahedron. Eight refers to the solid’s faces.
Fișa 68
Întrebare
Why does a lone pair in AX₄E favor an equatorial site over an axial site?
Răspuns
An equatorial site has two 90° interactions with other domains; an axial site has three. The equatorial choice reduces these close repulsions.
Fișa 69
Întrebare
Which common AXE cases give a linear molecular shape with two or five total domains?
Răspuns
AX₂ with two domains, and AX₂E₃ with five domains. A linear shape alone does not determine the electron geometry.
Fișa 70
Întrebare
Which bond angles occur in an idealized square-pyramidal AX₅E arrangement?
Răspuns
90° and 180°. Actual angles can deviate from these octahedral parent benchmarks.
Fișa 71
Întrebare
A VSEPR center is square planar with six total domains. What is its AXE notation?
Răspuns
AX₄E₂.
Fișa 72
Întrebare
A learner assigns every bent molecule the same bond angle. What information are they missing?
Răspuns
The electron-domain arrangement and the particular molecule. Bent includes AX₂E and AX₂E₂, and actual angles depend on the species.
Fișa 73
Întrebare
A learner calls NH₃ tetrahedral because nitrogen has four domains. What shape distinction resolves the error?
Răspuns
Tetrahedral is its electron geometry. Its molecular geometry is trigonal pyramidal because only the three bonded atoms define that shape.
Fișa 74
Întrebare
Why can four bonded atoms give tetrahedral AX₄ but square planar AX₄E₂?
Răspuns
AX₄ has four total domains. AX₄E₂ has six total domains, with two opposite lone pairs in an octahedral arrangement.
Fișa 75
Întrebare
Which ideal parent angles are the benchmarks for an AX₄E seesaw arrangement?
Răspuns
90°, 120°, and 180° from trigonal-bipyramidal electron geometry. Lone-pair repulsion can distort the actual bond angles.
Fișa 76
Întrebare
What molecular shape does VSEPR predict for an isolated PF₅ molecule?
Răspuns
Trigonal bipyramidal. Phosphorus has five bonded fluorine atoms and no lone pairs.
Fișa 77
Întrebare
What is the electron geometry around A in AX₂E₂?
Răspuns
Tetrahedral: two bonding domains plus two lone-pair domains.
Fișa 78
Întrebare
Which X–A–X bond angles occur in an ideal square-planar AX₄E₂ arrangement?
Răspuns
90° between adjacent bonds and 180° between opposite bonds.
78 de fișe
VSEPR Flashcards: Molecular Geometry & Bond Angles
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