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Author: Sarah Parkes

Cat Links Organic chemistry

Stereoisomerism and the Cahn, Ingold, Prelog rules

Posted on July 14, 2022January 7, 2025 Sarah Parkes

Alkenes cannot rotate through their C=C double bond, it locks the structure of the molecule in place at that point.

Continue readingStereoisomerism and the Cahn, Ingold, Prelog rules

Cat Links Calculations, Exam question practice, Organic chemistry

CFCs and the ozone layer

Posted on July 13, 2022March 1, 2025 Sarah Parkes

The chemistry that underlies the depletion of ozone in the stratosphere by chlorofluorocarbon molecules is really interesting – an application

Continue readingCFCs and the ozone layer

Cat Links Inorganic chemistry, Physical chemistry

Heterogeneous catalysis and catalytic converters

Posted on July 13, 2022October 2, 2024 Sarah Parkes

Catalysts are able to lower the activation enthalpy, Ea, for a reaction, increasing the number of successful collisions between reactants

Continue readingHeterogeneous catalysis and catalytic converters

Cat Links Organic chemistry

What is photochemical smog and how do we prevent it from forming?

Posted on July 12, 2022January 23, 2025 Sarah Parkes

Photochemical smog is a brownish haze caused by the action of the sun’s visible and ultraviolet radiation on the primary

Continue readingWhat is photochemical smog and how do we prevent it from forming?

Cat Links Physical chemistry

The Greenhouse Effect

Posted on July 11, 2022October 2, 2024 Sarah Parkes

Global warming and the greenhouse effect are topics that everyone feels they know well enough (because you’ve done them to

Continue readingThe Greenhouse Effect

Cat Links Organic chemistry

What are free radical substitution reactions?

Posted on July 11, 2022January 23, 2025 Sarah Parkes

Alkanes are exceptionally boring and unreactive molecules chemically speaking but we can persuade them to react with halogens in the

Continue readingWhat are free radical substitution reactions?

Cat Links Organic chemistry

Why do we need to blend petrol?

Posted on July 11, 2022January 6, 2025 Sarah Parkes

Petrol needs to be blended to have the right properties in terms of its volatility and to reduce its propensity

Continue readingWhy do we need to blend petrol?

Cat Links Organic chemistry

Fractional distillation and catalytic cracking explained

Posted on July 11, 2022January 6, 2025 Sarah Parkes

Crude oil is the raw material from which alkanes are extracted via the process of fractional distillation. There is nothing

Continue readingFractional distillation and catalytic cracking explained

Cat Links Organic chemistry

Structural isomerism

Posted on July 6, 2022October 2, 2024 Sarah Parkes

Structural isomers are molecules with the same molecular formula but a different arrangement of atoms … you need to recognise

Continue readingStructural isomerism

Cat Links Organic chemistry

How to name an alkane

Posted on July 6, 2022October 2, 2024 Sarah Parkes

I’ve tried to simplify the rules for naming alkanes in this video – I don’t think this requires notes so

Continue readingHow to name an alkane

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