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