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