Carbon & its Compounds

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Content

• Origin of Organic Chemistry
• Why there is a need for the study of Organic Chemistry
• Carbon and its position in the Periodic table.
• Bonding in carbon.
• Why carbon is so unique?
• Property of carbon

1. Tetravalent
2. Catenation
3. Isomerism Allotropes

• Hydrocarbons
• Types of hydrocarbon ( Saturated and Unsaturated Hydrocarbon)
• Functional group
• Nomenclature
• Homologous series
• Chemical properties
• Difference between soap and detergent
• Cleansing action of soap.

Origin of Organic Chemistry

• The term ‘organic’ originates from the Greek word ‘Organikos’, relating to the organ of a body.

• Vital Force Theory is a theory given by the Scientist Berzelius in 1809 which assumed that organic compounds are only formed in living cells and it is impossible to prepare them in laboratories.

• Berzelius’s Vital Force Theory, suggesting organic compounds could only form in living organisms, was disproven by Wohler’s in 1828.

• This marked a turning point, showing organic compounds could be made in laboratories without a vital force.

Friedrich Wohler’s first synthesised an organic compound

• In 1828, Friedrich Wohler, a German scientist, prepared ammonium cyanate (NH₄CNO) from ammonium chloride (NH₄Cl).

• Coincidentally, this synthesis led to the formation of urea CO(NH₂)₂, the first organic compound synthesized in a laboratory from purely inorganic materials, refuting the Vital Force Theory.

Δ

NH₄CNO —–> NH₂ – CO – NH₂

(ammonium (Urea)
cyanate)

Note: Urea (First organic compound synthesized in laboratory)

ORGANIC CHEMISTRY

• Organic compounds typically contain carbon-hydrogen or carbon-carbon bonds.
• Organic chemistry is the branch of chemistry focused on the study of carbon-containing compounds.

• However, there are exceptions, such as carbonates (CO₃^-2) and oxides (CO₂, CO), which contain carbon but are not considered organic compounds due to their distinct chemical properties.

Why There Is Need For Study Of Organic Chemistry

• The Earth’s atmosphere indeed contains a relatively low percentage of carbon in the form of carbon dioxide (CO₂), which is about 0.04% by volume.
• However, Carbon has the ability to team up with elements like hydrogen, oxygen, and nitrogen, due to the property of catenation, creating lots of different compounds, both basic and complex.
• This is super important in organic chemistry and is the reason for many natural and man-made carbon-based materials.
• We study organic chemistry to learn and control carbon compounds, vital in biology, medicine, materials, and daily stuff.

Carbon Compound

• Carbon is the main element present in all living organisms. Carbon can form a large number of compounds.

For Example –

• Food, Body, Medicine, Books, Fuels and so on.

Carbon and it’s Position In Periodic Table

• Symbol : C
• Position of C in the periodic table : ₆C¹²
• Atomic number : 6
• Mass number : 12
• Electronic configuration : 2,4
• Period : 2
• Group number : 14

Bonding In Carbon

• Bond is basically the force of attraction between two atoms.

• But have you ever thought about why there is a need to form bonds?

• Bonds form to create connections between atoms, allowing them to share or exchange electrons, which stabilizes molecules and helps elements achieve a more stable, lower-energy state.

• Carbon (C) has 4 electrons in its outermost shell; hence, it has a tendency to form covalent bonds by sharing its electrons with other atoms.

Properties of carbon

• Carbon is a unique element with a wide range of properties that make it essential for life and a key component of organic compounds.

• Tetravalent: Forms four covalent bonds for complex molecules.
• Versatile Bonding: Makes single, double, or triple bonds with various elements.
• Allotropes: Exists as diamond, graphite, graphene, and more.
• Macromolecules: Forms long chains and rings, creating diverse organic compounds.
• Nonmetal: Lacks metallic properties.
• Stable Bonds: Strong carbon-carbon bonds in organic molecules.
• Hydrocarbons: Basis of organic chemistry and fossil fuels.

Allotropes Of Carbon

• Allotropy is the property of an element in which the elements exist in more than one physical form having similar chemical properties but different physical properties.

• Important allotropes of carbon include diamond, graphite, and fullerene.

Diamond

Graphite

Fullerene

Diamond

• Each carbon atom is bonded to four other carbon atoms.
• It forms a rigid 3-D structure.
• Tetrahedral structure

• Diamonds can be synthesized by subjecting pure carbon to very high pressure and temperature.
• Hardest naturally occurring material known.

• Uses –

1. In Jewellery
2. In Industries

Graphite

• Each carbon atom is bonded to three other carbon atoms.
• It has layered structure.
• Hexagonal arrays being placed in layers one above the other.
• Black and opaque.
• Smooth and slippery.
• Good conductor of electricity.

• Uses –

1. Graphite used in making pencil
2. Graphite help in making graphene sheet

Fullerene

• Buckminster fullerenes is an important allotropes of carbon in which the C- atom is held together by covalent bond.
• The first fullerene to be identified was C-60.
• It forms a cage-like structure in which a 60 C atom is arranged in a spherical bond.
• This structure has 20 hexagon sand 12 Pentagons just like in football.

• Uses –

1. Super Conductor
2. Medicine Cosmetics.

HYDROCARBONS

Number of Carbon atoms	Root Word (Greek name)
One carbon atom    C1	Meth
Two carbon atoms  C2	Eth
Three carbon atoms C3	Prop
Four carbon atoms C4	But
Five carbon atoms C5	Pent
Six carbon atoms C6	Hex
Seven carbon atoms C7	Hept
Eight carbon atoms C8	Oct
Nine carbon atoms  C9	Non
Ten carbon atoms C10	Dec

Functional Group

• The functional group is defined as an atom or group of atoms joined in a specific manner responsible for the organic compounds’ characteristic chemical properties.

• Double and triple bonds are also considered as a functional group.

Type of Compound	General Formula	Description / Notes

Hydrocarbon

R–H

Basic organic compound

Alcohol

R–OH

R is any alkyl chain

Aldehyde

R–CHO

Contains –CHO functional group

Carboxylic Acid

R–COOH

Contains –COOH functional group

Haloalkane (Halogen derivative)

R–X

X = F, Cl, Br, I

Ketone

R–CO–R

Carbonyl group between two alkyl groups

Characteristics of functional groups–

• Compounds having same functional group have similar chemical properties.

• Compounds of different functional groups have different physical and chemical properties.

Note:- Functional groups are key structural features in organic compounds that categorize them into distinct classes or families. Compounds sharing the same functional group belong to the same class.

FUNCTIONAL GROUP	ABBREVIATION	GENERAL FORMULA	SUFFIX	PREFIX
CARBOXYLIC ACID	-COOH	CnH(2n+1) COOH	-oic acid	-carboxy
ALDEHYDE	-CHO	CnH(2n+1) CHO	-al	-aldo
KETONE	-(CO)-	CnH2nO	-one	-keto
HYDROXY	-OH	CnH(2n+1) OH	-ol	-hydroxy
ALKENE	C=C	CnH2n	-ene	–
ALKYNE	C≡C	CnH(2n-2)	-yne	–
HALOGEN	-X	CnH(2n+1)X	–	-halo
ALKYL	-R	CnH(2n+1)	–	-alkyl

NOMENCLATURE

• Each and every object in this universe is identified by its name.
• Nomenclature is the system of assigning a name to a compound.
• Naming systems are classified into two and they are-
  
  1. Common or trivial system
  
  Based on historical names.
  
  Often derived from properties or sources.
  
  Varies by region, causing confusion.
  
  Examples: Water (H₂O), table salt (sodium chloride, NaCl), vinegar (acetic acid, CH₃COOH).

2. IUPAC ( International Union of Pure and Applied Chemistry).

The IUPAC system is a systematic and internationally recognized method for naming chemical compounds.

It is based on a set of rules and guidelines that ensure a unique name for each compound.

IUPAC names are universally accepted.

For example, the IUPAC name for common table salt is sodium chloride.

• Root word –  It depends upon the number of carbon atoms present in the longest carbon chain selected.
• For Example- ‘Pent’ refers to a chain with 5 carbon atom.

• Suffix – The suffix in IUPAC nomenclature specifies the type of functional group and nature of the bond in a carbon-carbon atom present in the compound.

• C-C( Single bond) – Alkane  (C_nH_(2n+2))

• C=C(Double bond) – Alkene  (C_nH_2n)

• C≡C( Triple bond) – Alkyne ( C_nH_(2n-2))

• Alkyl- (C_nH_(2n+1))

• Functional group

• Prefix – It denotes the substituents, alkyl or functional group and its position in the carbon chain.

NOMENCLATURE – RULES

• Select the parent chain –

1. Identify the longest continuous chain of C atom.
2. The longest chain need not to be straight.

• Branches or Substituents:

The branched-chain is considered to be substituents, and their positions are indicated by the number of carbon to which they are attached.

• Numbering Carbon Atoms:

1. Carbon atoms in the chain are numbered in such a way that functional groups or substituents should get the lowest possible number.
2. Always prioritize the functional group over the substituent.

• Prefixes for Substituents:

Use prefixes to name substituent groups (alkyl or alkane groups) attached to the parent chain. Common prefixes include methyl, ethyl, and propyl.

• Position of Substituents:

The position of the alkyl group is indicated by writing its name and position before the parent hydrocarbon’s name.

When writing an IUPAC name, remember to use hyphens between “number” and “numerals” and commas between numbers.

• Suffix for Functional Groups:

Add a suffix to the root word of the parent chain to indicate the functional group. Common suffixes include ane for single bonds, ene for double bonds, and yne for triple bonds.

• Position of functional group:

The position of the functional group is indicated by writing the position