Carbon and its compounds Flashcards
Atomic number of carbon?
6
Electronic configuration (2,4)
Can carbon gain or lose 4 electrons to become stable?
Carbon cannot reach C+4 state or C-4 state by losing or gaining 4 electrons.
why cant carbon reach C+4 state or C-4 state?
It could lose 4 electrons forming C+4 state but it would require a large amount of energy to remove 4 electrons.
It could gain 4 electrons forming C-4 state but it would be difficult for nucleus of carbon to hold 4 extra electrons with 6 protons.
Unique nature of carbon?
Tetrahydral shape/Tetra valency: Carbon has 4 electrons in its outermost shell, so 4 covalent bonds can be formed.
Catenation property: A property in which carbon can make a chain of covalent bonds with n number of carbon atoms.
How does carbon show this unique property of catenation?
Carbon shows this property because of its size since it is smaller than other elements in the 14th group. Nucleus of carbon can hold the shared pair of electrons very strongly.
What are hydrocarbons?
Compounds compromising of hydrogen and carbon only. Types:
Saturated, Unsaturated.
What are saturated hydrocarbons?
Hydrocarbons which have carbon-carbon single bond. Consist of alkanes.
General formula is CnH2n+2
Methane, Ethane, Propane
What are unsaturated hydrocarbons?
Hydrocarbons which have carbon-carbon double or triple bonds. Consist of alkenes and alkynes.
Alkenes: CnH2n carbon-carbon double bond.
Methene, Ethene, Propene
Alkynes: CnH2n-2 carbon-carbon triple bond.
Methynes, Ethyne, Propyne
Allotrophy?
Phenomenon in which an element like carbon can exist in various forms having different physical properties but identical chemical properties. Eg:
Diamond, Fullerene, Graphite are allotropes of carbon
Why is Diamond hard?
Diamond is hard because each carbon atom in diamond satisfies its valency with 4 other carbon atoms only.
Why does graphite conduct electricity?
Graphite can conduct electricity because there is a weak bond in graphite as it satisfies its 4 valency with 3 carbon atoms only. It also allows free movement of electrons.
Structural isomers/Isomerism?
Compounds with identical molecular formula but different structures. Types:
Straight/N- chain, Branched chain, Ring structure.
Functional groups?
An atom or a group of atoms that make a carbon atom reactive and decides its chemical properties.
Halogens, Alcohols, Aldehydes, Ketones, Carboxylic acids.
Alcohols functional group?
-OH
Aldehydes functional group?
C double bond O single bond H
H-C=O
Ketones functional group?
Attached in middle. First ketone member is propanone.
C=O
Carboxylic acid functional group?
C double bond O single bond OH
OH-C=O
Homologous series?
Group of organic compounds having similar structure and chemical property in which successive group differ by CH2 or 14u.
Chemical properties of hydrocarbons?
Combustion
Oxidation
Addition
Substitution
Combustion?
A reaction in which a substance burns with excess of O₂ to give CO₂ and H₂O.
CH₄ + O₂→ CO₂ + H₂O
C₂H₆ + O₂ → CO₂ + H₂O
Complete combustion gives blue flame.
Lack of O₂ give yellow/orange flame.
Oxidation reaction?
A reaction in which alcohols are converted into carboxylic acids by oxidizing them with alk.KMnO₄ or acidified.K₂Cr₂O₇
C₂H₅OH → (in presence of alk.KMnO₄ or acidified K₂Cr₂O₇) CH₃COOH + H₂O
Addition reaction?
Unsaturated → Saturated Hydrocarbon
By adding hydrogen in presence of Ni/Pd.
Eg: Ethene → Ethane
Propyne → Propene
Hydrogenation reaction?
Reaction in which there is addition of hydrogen to remove double bond, it is known as hydrogenation reaction. Used in vegetation of oil.
Substitution reaction?
Reaction in which hydrogen is replaced by any halogen in presence of sunlight.
CH₄ + Cl₂ → CH₃Cl+ HCl
