Chemistry of Carbon Chemistry of Carbon CompoundsCompounds

Properties of CarbonAllotropesInorganic Compounds of CarbonOrganic Chemistry

CARBONCARBON

non-metallic element of group IV-A which non-metallic element of group IV-A which constitutes only about 0.009 % by mass constitutes only about 0.009 % by mass of Earth’s crust. (but it is the 6of Earth’s crust. (but it is the 6thth most most abundant element in the universe)abundant element in the universe)

exists in three isotopes: exists in three isotopes: 1212C, C, 1313C, C, 1414CC has the unique ability to form long chains has the unique ability to form long chains

(consisting of more than 50 C atoms) and (consisting of more than 50 C atoms) and stable five or six-membered rings called stable five or six-membered rings called catenation.catenation.  

Some Physical Properties of Some Physical Properties of CarbonCarbon

Atomic number: Atomic number: 66 Electron Configuration:Electron Configuration: 1s1s222s2s222p2p22

Atomic mass: Atomic mass: 12.0107 amu12.0107 amu Melting Point: Melting Point: 3,823 K3,823 K Boiling Point: Boiling Point: 4,098 K4,098 K Density: Density: 2.2670 g/cm2.2670 g/cm33

Phase (room temp.): Phase (room temp.): solidsolid

AllotropesAllotropes

two or more forms of the same two or more forms of the same element that differ significantly in element that differ significantly in chemical & physical properties.chemical & physical properties.

Allotropes of Carbon

Crystalline-Crystalline- have highly ordered 3D structure have highly ordered 3D structure1. graphite2. diamond3. fullerenes

AmorphousAmorphous1.1. carbon blackcarbon black2.2. charcoalcharcoal3.3. cokecoke

GraphiteGraphite

       

graphite is derived from the Greek graphite is derived from the Greek word “graphein” which means word “graphein” which means to to writewrite. It was named by the German . It was named by the German Geologist Abraham Werner in 1789. Geologist Abraham Werner in 1789.

Properties & Uses of Graphite

soft, greasy feel black mineralsoft, greasy feel black mineral is made up of layers of carbon, the Carbon atoms is made up of layers of carbon, the Carbon atoms

arranged in rings of 6 atoms.arranged in rings of 6 atoms. layers slide easily over each other because of layers slide easily over each other because of

the weak inter-layer forces (Van der Waal’s the weak inter-layer forces (Van der Waal’s forces) but inter atomic bonds are strong forces) but inter atomic bonds are strong covalent bondscovalent bonds

contains free electrons, which move along layerscontains free electrons, which move along layers good conductor of heat & electricitygood conductor of heat & electricity used as pencil lead, lubricants, electrodes & raw used as pencil lead, lubricants, electrodes & raw

material for making synthetic diamondsmaterial for making synthetic diamonds

DiamondDiamond

transparent crystalline solid, with high density compared to other carbon allotropes

hardest naturally occurring substance carbon atom is joined to 4 other Carbon

atoms, forming a Tetrahedron, or 4 sided figure held together by covalent bonds

used as cutting material, jewelries & for decorative purposes

FullerenesFullerenes

a class of carbon molecules in which the a class of carbon molecules in which the carbon atoms are arranged into 12 carbon atoms are arranged into 12 pentagonal faces and 2 or more pentagonal faces and 2 or more hexagonal faces to form a hollow sphere, hexagonal faces to form a hollow sphere, cylinder, or similar figure.cylinder, or similar figure.

the most prominent of the fullerenes is the most prominent of the fullerenes is buckminsterfullerenebuckminsterfullerene, a spheroidal , a spheroidal molecule, resembling a soccer ball, molecule, resembling a soccer ball, consisting of 60 carbon atoms. consisting of 60 carbon atoms.

FullerenesFullerenes

fullerene research is expected to lead to fullerene research is expected to lead to new materials, lubricants, coatings, new materials, lubricants, coatings, catalysts, electro-optical devices, and catalysts, electro-optical devices, and medical applications.medical applications.

were first identified in 1985 by R. F. Curl, were first identified in 1985 by R. F. Curl, Jr., R. E. Smally, and H. W. Kroto (who Jr., R. E. Smally, and H. W. Kroto (who shared the 1996 Nobel Prize in shared the 1996 Nobel Prize in Chemistry) Chemistry)

STRUCTURE OF GRAPHITESTRUCTURE OF GRAPHITE

STRUCTURE OF DIAMONDSTRUCTURE OF DIAMOND

STRUCTURE OF STRUCTURE OF BUCKMINSTERFULLERENBUCKMINSTERFULLEREN

EE

Carbon BlackCarbon Black

formed when hydrocarbons formed when hydrocarbons such as methane are heated such as methane are heated in a very limited supply of in a very limited supply of oxygen:oxygen:

CHCH44 + O + O22 C C(s)(s) + H + H22OO

used as pigment in black inks used as pigment in black inks and making automobile tiresand making automobile tires

CharcoalCharcoal

formed when wood is heated formed when wood is heated strongly in the absence of airstrongly in the absence of air

used in filters to remove offensive used in filters to remove offensive odors from air and colored or bad-odors from air and colored or bad-tasting impurities form watertasting impurities form water

CokeCoke

impure form of carbon formed when coal impure form of carbon formed when coal ((coalcoal- a fuel substance of plant origin, - a fuel substance of plant origin, largely or almost entirely composed of largely or almost entirely composed of carbon with varying amounts of mineral carbon with varying amounts of mineral matter) is heated strongly in the absence matter) is heated strongly in the absence of air.of air.

used as a reducing agent in metallurgical used as a reducing agent in metallurgical process.process.

Inorganic Compounds of Carbon

Oxides (carbon monoxide & carbon dioxide)

Carbonates Bicarbonates Carbides Cyanides

Carbon MonoxideCarbon Monoxide

a colorless, odorless, toxic gas formed a colorless, odorless, toxic gas formed by the incomplete combustion of by the incomplete combustion of carbon-containing compounds.carbon-containing compounds.

They are used for extracting nickels, They are used for extracting nickels, organic synthesis and production of organic synthesis and production of hydrocarbon fuels with hydrogenhydrocarbon fuels with hydrogen

Carbon DioxideCarbon Dioxide

a colorless, odorless, non-toxic gas.a colorless, odorless, non-toxic gas. it is an acidic oxide & used in it is an acidic oxide & used in

beverages, fire extinguishers, beverages, fire extinguishers, manufacture of baking soda, NaHCOmanufacture of baking soda, NaHCO33, ,

and soda ash, Naand soda ash, Na22COCO33..

COCO22 can also exist in solid form, called can also exist in solid form, called

“dry ice”, which is used as a refrigerant.“dry ice”, which is used as a refrigerant.

CarbonatesCarbonates

are compounds containing the are compounds containing the anion COanion CO33

2-2-

examples are calcium carbonate examples are calcium carbonate which can be found in egg shells, which can be found in egg shells, shells of marine organisms & in shells of marine organisms & in both limestone & marbleboth limestone & marble

CarbonatesCarbonates

Calcium carbonateCalcium carbonate is normally is normally water-insoluble. It will only dissolve in water-insoluble. It will only dissolve in water saturated with COwater saturated with CO22 because because carbonated water (or carbonic acid) carbonated water (or carbonic acid) reacts with calcium carbonate to form reacts with calcium carbonate to form calcium bicarbonate, which is water-calcium bicarbonate, which is water-soluble:soluble:

CaCOCaCO3(s)3(s) + H + H22COCO3(aq)3(aq) Ca Ca2+2+(aq)(aq) + 2HCO + 2HCO33

--(aq)(aq)

BicarbonatesBicarbonates

are compounds containing the anion HCOare compounds containing the anion HCO33-- example is example is sodium bicarbonatesodium bicarbonate or baking or baking

soda NaHCOsoda NaHCO33, a weak base added to recipes , a weak base added to recipes to neutralize the acidity of other to neutralize the acidity of other ingredients. Baking soda is a mixture of ingredients. Baking soda is a mixture of baking soda and a weak acid, like tartaric baking soda and a weak acid, like tartaric acid, that when mixed with water, the acid acid, that when mixed with water, the acid reacts with the HCOreacts with the HCO33

- - ion to form COion to form CO22 gas, gas, which causes the dough or batter to rise.which causes the dough or batter to rise.

HCOHCO33--((aqaq)) H H

++((aqaq)) H H22COCO3(3(aqaq)) H H22OO((ll)) + CO + CO2(2(gg))

CarbidesCarbides

ionic compounds formed from the ionic compounds formed from the combination of carbon & metalscombination of carbon & metals

examples are CaCexamples are CaC22 (“carburo”) and (“carburo”) and BeBe22C in which carbon is in the form of C in which carbon is in the form of CC22

2-2- or C or C4-4- ions which are strong ions which are strong Bronsted bases & reacts with water as:Bronsted bases & reacts with water as:

CC222-2-

(aq)(aq) + 2H + 2H22OO(l)(l) 2OH 2OH--(aq)(aq) + C + C22HH2(g)2(g)

CC4-4-(aq)(aq) + 4H + 4H22OO(l)(l) 4OH 4OH--

(aq)(aq) + CH + CH4(g)4(g)

CarbidesCarbides

another example is the covalent another example is the covalent compound of carbon with silicon compound of carbon with silicon called “carborundum” or silicon called “carborundum” or silicon carbide, SiC.carbide, SiC.

it is almost as hard as diamond & it it is almost as hard as diamond & it has the diamond structure which can has the diamond structure which can be prepared from the reaction:be prepared from the reaction:

SiOSiO2(s)2(s) + 3C + 3C(s)(s) SiC SiC(s)(s) + 2CO + 2CO(g)(g)

CyanidesCyanides

a carbon compound containing the a carbon compound containing the anion group :CNanion group :CNN:N:--

cyanide ions are extremely toxic cyanide ions are extremely toxic

used in the metallurgy of gold in the used in the metallurgy of gold in the form of NaCNform of NaCN