che 2c midterm 2 - tm & main grp

Sc

Common O.S. = 0, +3

- Some similar chemistry to Mg

- No d-electrons in ions: colorless & diamagnetic

Ti

Common O.S. = 0, +4

- Some similar chemistry to C, Si

- Structurally strong, very light weight metal

- Great for bicycle frames, airplanes

- TiO2 is very white: used as a brightener in paint & paper

V

Most common O.S. = 0, +5

- Used in alloys to strengthen material

- Toxic!

Nb & Ta

Named after Greek mythology daughter and father

- Nb is a material of interest for superconductors

Cr

Common O.S. = 0, +3, +4, +6

- First family with multiple oxidation s t a t e s found in nature

- Name derived from the greek word for color, "chroma"

- Toxic!

Mo and W

Biologically important for enzymes, pigments

- W has a very high melting point

- Used for light bulb filaments, heat lamps

Mn

• Most oxidation states

  • +2, +3, +4, +6, +7

    has the most oxidation states of first-row transition metals

- Not found in nature as a pure metal. - always in ore.

- Used as a catalyst, in alkaline batteries, strengthening component in steel, and as a cofactors to many enzymes

- Permanganates (Mn with alkali metals or alkaline earths, eg. KMnO4) are very strong oxidizing angents!

This transition metal has ground state valence electrons in the 3d orbitals. When fully oxidized, its oxidation state is +7

Tc (technetium)

Lightest radioactive element (a beta emitter)

- Only man made!

- Discovered in 1937

Fe

Possible O.S. = +2 to +6; common O.S. = +2, +3

- The most important element for modern civilization, because...

- Major component of steel (small amount of C, Mn, and others).

- Most common element on earth by mass.

- Biological importance for oxygen transport

in vertebrates, redox enzymes in plants

and animals

Co

• Common OS = +2, +3

• Beautiful blue color for glass, dyes

- Very rare to find pure; more common in ores (with toxic

a n d smelly byproducts). B e c a m e known

as "goblin" ore, "kobold" in German.

Rh (Rhodium)

Hard, corrosion resistant, chemically inert.

- Very rare!

- Excellent metal for plating jewelry.

Ir

Rare, much of it comes from outer

Archeologists use Ir as a tracer to develop and support theories about when asteroids hit Earth.

Ni

applications: coins, batteries, corrosion preventer

Pt

Rare, very unreactive, corrosion resistant.

Applications of Pt: intert electrodes,

jewelry, anti-cancer drugs

(eg. cis-platin for

chemotherapy)

Cu

• Common OS = +1, +2

• excellent conductor of electricity, durable (various electrochemistry applications)

Alloys: C u / S n Bronze

C u / Z n B r a s s

Ag

Has the highest thermal conductivity, electrical conductivity, and reflectivity.

- More abundant than Au (but, more of it is naturally occurring as ores and oxides than Au.)

- Tarnishes from contact with sulfur

Au

Very unreactive,

Even to most acids

Most malleable metal

- Used for jewelry,

currency, etc.

Zn

• Common OS = +2

• Similar chemistry to Mg

• Corrosion resistant. Also toxic!

Cd

Toxic. Common O.S. = +2, used in batteries.

Hg

The only metal that is liquid at Room Temperature.

Also toxic (based on dose)

Application in dental fillings (Ag Hg amalgam)

Li

important for current battery technologies

2019 Nobel Prize went to scientists who pioneered Li-batteries

Alkali Metals

Li, Na, K, Rb, Cs, Fr

Common O S = +1

Highly reactive (valence electron is easily given up.)

react vigorously with water to make H, gas.

H

Lightest element, escapes from earth's gravity

Small, low IMFs, liquifies at 20 K

Applications: Rocket fuel

N o n - m e t a l

Alkaline Earth Metals

Be, Mg, Ca, Sr, Ba, Ra

Common O S = + 2

Low densities, low melting & boiling

points, low solubility, form basic oxides

Be

smaller, harder, higher melting point, higher ionization energy,

more covalent bonding, less reactive than family members,

amphoteric oxide

Mg, Ca

Biologically important!

Lower solubility = hard water

Ba

Toxic, absorbs X-rays

Not very soluble at low conc.

Useful tool for gastromedicine.

Ra

Radioactive!

Group 13

B, Al, Ga, In, Tl

Common OS = +1, +3

Metals are soft, relatively reactive

Aluminum oxide

(Al,, corundum structure) is the basis for

various precious gems ; small amounts of transition metals

determine color (d-to-d transitions in action!)

B

not a metal

Supports 6 e- in valence

Can form dimers

Chemistry similar to Si

Ga

higher density liquid,

low melting point.

This metal is solid at room temperature, but will melt in your hand. Its elemental form has one electron in its p-orbitals.

Group 14

C, Si, Ge, Sn, Pb

Common OS = +2, +4 (and -4, C and Si)

Can form 4 covalent bonds to non-metals

C

can form pi bonds; basis for life.

Allotropes: diamond, graphite, fullerenes

Si

Si-O bonds stronger then Si-Si bonds.

Basis for geological world.

Ge

Rare, semiconductors

Sn

Soft metal, silvery color.

Allotropes: White tin, grey tin

brittle tin.

This metal has several allotropes. At room temperature it is a relatively robust solid, but at low temperatures it disintegrates. Common oxidation states include +2 and +4. It is alloyed with lead and antimony for use as solder in electronic devices.

Pb

Soft, toxic, low melting point

Group 15

N, P, As, Sb, Bi

Common OS = Multiple!

N:

Stable or highly reactive

(Na VS. Trinitrotoluene / TNT)

Can form pi bonds: Important for DNA, nitrogen fixation processes, atmospheric reactions.

P

Larger, d-orbitals available for electrons,

bonding. Present in ATP, ADP, also important component of fertilizer.

As

Toxic, semi-metal

It has common oxidation states of +5, +3, 0, and -3.

Bi

Heavy, not very toxic.

Good substitute for lead in some applications.

Group 16

O, S, Se, Te, Po

Common O.S. = 0 (0), -1 (peroxides), -2 (most common for the family)

For alkali metals: LiO (oxide), Na, O, (peroxide), and MO, (M = K, Rb, Cs, superoxides)

O

Found in two molecular forms: O, and 03

O i s toxic! Used for water treatment; also important role in upper atmosphere.

S

Unpleasant smell. Many uses,

including chemical weapons.

Over 30 solid allotropes!

Makes a ring structure.

Po

Radioactive, lethal,

also present in tobacco.

Group 17: Halogens

F, Cl, Br, 1, At

CFCS → Chlorofluorocarbons

Common O.S. = -1

Atomic form not found in nature - diatomic

High electronegativity, form polar covalent bonds.

With oxygen, form oxyacids:

Examples: HCO, H C , H C , HCO

F

Small, highest electronegativity

Important for dental care, gives CFCs and PFAS stability

At

Radioactive, longest lived

isotope lasted 8.3 h.

Group 18: Noble Gases

He, Ne, Ar, Kr, Xe, and Rn

Common O.S. = 0, can b e different.

Typically low reactivity. Colorless, odorless, neutral.

Low melting point, low boiling point.

He

Forms no compounds. Light! Escapes our atmosphere.

Important for experiments; scientists concerned of a shortage!

Ne

No compounds; luminescent with current.

Ar

Major component of air.

Forms some compounds.

Kr and Xe and Rn

Many

stable compounds possible

with expanded octets!

Rn

Radioactive

Os

This third-row transition metal has common oxidation states of +2, +3, +4, and (when fully oxidized) +8.

Se

This element has common oxidation states of +4, +6, and -2. Its highest occupied valence orbital in the ground state is the 4p.

Y

This second-row transition metal has common oxidation states of 0 and +3, and forms colorless compounds in solution

Na

This main group metal is highly reactive with water. Its ionic form is present in high concentrations in the ocean and in processed foods

Tl

This 6th period main group metal is quite toxic and has common oxidation states of +1 and +3

K

This metal reacts vigorously with water, forming H2 gas. It has a low ionization energy and low electronegativity, and valence orbitals at level n = 4.