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