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Author: Sarah Parkes

Cat Links Organic chemistry

Why are carrots orange?

Posted on September 23, 2025September 24, 2025 Sarah Parkes

The short answer is because they contain the pigments β-carotene and lycopene which strongly absorb visible light in the blue-green

Continue readingWhy are carrots orange?

Cat Links Organic chemistry

Explaining the reactivity of substituted benzenes

Posted on September 23, 2025September 23, 2025 Sarah Parkes

What happens when a substituted benzene such as chlorobenzene or methyl benzene undergoes an electrophilic substitution reaction? There are two

Continue readingExplaining the reactivity of substituted benzenes

Cat Links Organic chemistry

Friedel-Crafts reactions in benzene

Posted on September 22, 2025September 22, 2025 Sarah Parkes

Friedel-Crafts reactions allow us to add alkyl and acyl groups to benzene providing a way of adding carbon atoms to

Continue readingFriedel-Crafts reactions in benzene

Cat Links Organic chemistry

Electrophilic substitution reactions of benzene

Posted on September 22, 2025September 22, 2025 Sarah Parkes

At first sight benzene seems surprisingly unreactive for an unsaturated hydrocarbon. Benzene does not decolourise bromine water when shaken with

Continue readingElectrophilic substitution reactions of benzene

Cat Links Biochemistry, Organic chemistry

How do enzymes catalyse reactions?

Posted on August 19, 2025August 19, 2025 Sarah Parkes

Enzymes are proteins that catalyse virtually all the biochemical reactions happening in the body, working at body temperature (37°C) and

Continue readingHow do enzymes catalyse reactions?

Cat Links Biochemistry, Organic chemistry

What is optical isomerism?

Posted on August 15, 2025August 19, 2025 Sarah Parkes

Optical isomerism is a type of stereoisomerism in which the optical isomer has a chiral centre and does not possess

Continue readingWhat is optical isomerism?

Cat Links Biochemistry, Organic chemistry

Understanding the structure of proteins

Posted on August 13, 2025August 19, 2025 Sarah Parkes

The primary structure of a protein is simply the sequence of amino acids in a polypeptide chain, but these polypeptide

Continue readingUnderstanding the structure of proteins

Cat Links Biochemistry, Organic chemistry

Amino acids and polypeptides

Posted on August 13, 2025August 19, 2025 Sarah Parkes

Amino acids are the building blocks of polypeptide chains which fold into 3D protein structures. Proteins are biopolymers that play

Continue readingAmino acids and polypeptides

Cat Links Biochemistry, Organic chemistry

The chemistry of fats, oils and soap

Posted on August 5, 2025August 19, 2025 Sarah Parkes

Fats and oils have the same basic chemical structure – they are all esters of propane-1,2,3-triol (glycerol) bonded to long

Continue readingThe chemistry of fats, oils and soap

Cat Links Organic chemistry

Bioplastic vs. biodegradable plastic – what’s the difference?

Posted on August 4, 2025August 11, 2025 Sarah Parkes

It is estimated that approximately 6300 Mt of plastic waste has been generated since the 1950s, of which around 9%

Continue readingBioplastic vs. biodegradable plastic – what’s the difference?

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  • Why are carrots orange?
  • Explaining the reactivity of substituted benzenes
  • Friedel-Crafts reactions in benzene
  • Electrophilic substitution reactions of benzene
  • How do enzymes catalyse reactions?

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