Organic Reactions: Addition and Substitution

Dr. English introduces organic chemistry reactions, focusing on substitution and addition reactions. Substitution reactions involve replacing an atom or group in a molecule, with examples like halogen substitution in hydrocarbons. Addition reactions involve adding atoms to unsaturated hydrocarbons, converting them to saturated ones, such as hydrogenation. The video provides examples and emphasizes the importance of functional groups in organic reactions.

What is the primary focus of organic reactions discussed in the introduction?

• Reactions of inorganic compounds

• Nuclear reactions

• Substitution and addition reactions

• Reactions involving metals

In substitution reactions, what typically replaces a hydrogen atom in a saturated hydrocarbon?

• Oxygen atom

• Nitrogen atom

• Carbon atom

• Halogen atom

What is formed when chlorine gas reacts with methane in a substitution reaction?

• Chlorine dioxide and methane

• Methanol and chlorine

• Chloromethane and water

• Chloromethane and hydrogen chloride

What is the molecular formula for chloromethane?

• C2H6

• CH4

• CH3Cl

• C2H5Cl

What is a key difference between substitution and addition reactions?

• Substitution reactions involve breaking double bonds

• Addition reactions occur in saturated hydrocarbons

• Addition reactions involve adding atoms to unsaturated hydrocarbons

• Substitution reactions require a catalyst

What is required for hydrogenation in addition reactions?

• Presence of water

• High pressure and low temperature

• Presence of a catalyst and elevated temperatures

• Absence of light

In the addition reaction example, what happens to the double bond in ethene?

• It forms a ring structure

• It becomes a triple bond

• It remains unchanged

• It is broken to form a single bond

What is the product formed when ethene reacts with chlorine gas in an addition reaction?

• Dichloroethane

• Chloroform

• Chloromethane

• Ethyl chloride

What is the molecular formula for the product of ethene and chlorine gas reaction?

• C2H4Cl2

• C2H6

• C2H5Cl

• C2H3Cl

What is the role of chlorine in the addition reaction with ethene?

• It breaks the double bond and adds to the carbons

• It forms a new double bond

• It acts as a catalyst

• It removes hydrogen atoms