Chem Midterm 2

Ammonium

NH₄⁺ (charge +1)

Hydronium

H⁺ / H₃O⁺ (charge +1)

Acetate

CH₃COO^- / C₂H₃O₂^- (charge -1)

Cyanide

CN^- (charge -1)

Dihydrogen Phosphate

H₂PO₄^- (charge -1)

Hydrogen Carbonate (Bicarbonate)

HCO₃^- (charge -1)

Hydroxide

OH^- (charge -1)

Nitrate

NO₃^- (charge -1)

Nitrite

NO₂^- (charge -1)

Permanganate

MnO₄^- (charge -1)

Thiocyanate

SCN^- (charge -1)

Perchlorate

ClO₄^- (charge -1)

Chlorate

ClO₃^- (charge -1)

Chlorite

ClO₂^- (charge -1)

Hypochlorite

ClO^- (charge -1)

Bromine Analog for Hypochlorite

Hypobromite: BrO^- (charge -1)

Bromine Analog for Chlorite

Bromite: BrO₂^- (charge -1)

Bromine Analog for Chlorate

Bromate: BrO₃^- (chagre -1)

Bromine Analog for Perchlorate

Perbromate: BrO₄^- (charge -1)

Iodine Analog for Hypochlorite

Hypoiodite: IO^- (charge -1)

Iodine Analog for Chlorite

Iodite: IO₂^- (charge -1)

Iodine Analog for Chlorate

Iodate: IO₃^- (charge)

Iodine Analog for Perchlorate

Periodate: IO₄^- (charge -1)

Hypo-…-ite

1 oxygen (-1 charge)

…-ite

2 oxygens (-1 charge)

…-ate

3 oxygens (-1 charge)

per-…-ate

4 oxygens (-1 charge)

Carbonate

CO₃^-2 (-2 charge)

Chromate

CrO₄^-2 (-2 charge)

Dichromate

Cr₂O₇^-2 (-2 charge)

Hydrogen Phosphate

HPO₄^-2 (-2 charge)

Oxalate

C₂O₄^-2 (-2 charge)

Peroxide

O₂^-2 (-2 charge)

Thiosulfate

S₂O₃^-2 (-2 charge)

Sulfate

SO₄^-2 (-2 charge)

Sulfite

SO₃^-2 (-2 charge)

Phosphate

PO₄^-3 (-3 charge)

What determines the charge of monatomic ions from main group elements?

Their group on the periodic table, b/c they gain/lose e^- to reach a noble gas configuration

What charge do Group 1 elements form?

+1

What charge do Group 2 elements form?

+2

What charge do Group 15 elements form?

-3

What charge do Group 16 elements form?

-2

What charge do Group 17 elements form

-1

What is the common ionic charge of Zinc

Zn²⁺

What is the common ionic charge of Cadmium?

Cd²⁺

What is the common ionic charge of Nickel (in its single common state)?

Ni²⁺

What is the common ionic charge of Silver?

Ag⁺

What is unusual about the Mercury(I) cation?

It forms a diatomic ion: Hg₂²⁺ instead of single Hg⁺ ions

Mega-

M, 10⁶

Kilo-

k, 10³

Deci-

d, 10^-1

Centi-

c, 10^-2

Milli-

m, 10^-3

Micro-

µ, 10^-6

Nano-

n, 10^-9

Pico-

p, 10^-12

What is steric number?

Number of bonded atoms + lone pairs on the central atom

What deterermines molecular shape?

Electron geometry minus lone pairs (only look at atoms)

Steric # = 2 (bonded atoms + lone Pairs)

Electron Geometry: Linear

Bonded Atoms: 2
Lone Pairs: 0

Molecular Shape: Linear

Bond Angle: 180º

Steric # = 3, 0 lone pairs (bonded atoms + lone Pairs)

Electron Geometry: Trigonal Planar

Shape: Trigonal Planar

Bond Angle: 120º

Steric # = 3, 1 lone pair (bonded atoms + lone Pairs)

Electron Geometry: Trigonal Planar

Shape: Bent

Bond Angle: <120º

Steric # = 4, 0 lone pairs (bonded atoms + lone Pairs)

Electron Geometry: Tetrahedral

Shape: Tetrahedral

Bond Angle: 109.5º

Steric # = 4, 1 lone pair (bonded atoms + lone Pairs)

Electron Geometry: Tetrahedral

Shape: Trigonal Pyramidal

Bond Angle: <109.5º

Steric # = 4, 2 lone pairs (bonded atoms + lone Pairs)

Electron Geometry: Tetrahedral

Shape: Bent

Bond Angle: <109.5º

Steric # = 5, 0 lone pairs (bonded atoms + lone Pairs)

Electron Geometry: Trigonal Bipyramidal

Shaoe: Trigonal Bipyramidal

Angles: 120º (equatorial), 90º (axial)

Steric # = 5, 1 lone pair (bonded atoms + lone Pairs)

Electron Geometry: Trigonal Bipyramidal

Shape: Seesaw

Angles: <120º, <90º

Steric # = 5, 2 lone pairs (bonded atoms + lone Pairs)

Electron Geometry: Trigonal Bipyramidal

Shape: T-shaped

Angles: <90º

Steric # = 5, 3 lone pairs (bonded atoms + lone Pairs)

Electron Geometry: Trigonal Bipyramidal

Shape: Linear

Angle: 180º

Steric # = 6, 0 lone pairs (bonded atoms + lone Pairs)

Electron Geometry: Octahedral

Shape: Octahedral

Angle: 90º

Steric # = 6, 1 lone pair (bonded atoms + lone Pairs)

Electron Geometry: Octahedral

Shape: Square Pyramidal

Angle: <90º

Steric # = 6, 2 lone pairs (bonded atoms + lone Pairs)

Electron Geometry: Octahedral

Shape: Square Planar

Angle: 90º

What counts as ONE electron group

Single bond, double bond, triple bond, or lone pair = 1 group

Do multiple bonds change shape counting

No. Double/triple bonds still count as one region

What repels more: bonds or lone pairs?

Lone pairs repel more strongly

Order of repulsion strength

LP-LP > LP-BP >BP-BP

When is a molecule NONPOLAR

• Symmetrical shape

• No lone pairs on central atom

• Identical surrounding atoms

When is a molecule POLAR

• Lone pairs distory symmetry or

• Different surrounding atoms

Shapes without lone pairs (the '“perfect” shapes)

Linear → Trigonal Planar → Tetrahedral → Trigonal Bipyramidal → Octahedral