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Author: Sarah Parkes

Cat Links Calculations, Physical chemistry

How to calculate the pH of a base

Posted on April 28, 2022April 24, 2025 Sarah Parkes

Once again, we can assume that strong bases are fully dissociated in solution so the concentration of OH– is the

Continue readingHow to calculate the pH of a base

Cat Links Calculations, Physical chemistry

How to calculate the pH of strong acids and weak acids

Posted on April 26, 2022August 28, 2025 Sarah Parkes

The strength of an acid (HA) is determined by its ability to donate protons or H+ ions to water. The [H+(aq)]

Continue readingHow to calculate the pH of strong acids and weak acids

Cat Links Physical chemistry

What is the ionic product of water?

Posted on April 26, 2022April 24, 2025 Sarah Parkes

Water self-ionises – essentially it reacts with itself to very small extent. We know this because even pure water has

Continue readingWhat is the ionic product of water?

Cat Links Physical chemistry

What are conjugate acid-base pairs?

Posted on April 26, 2022November 18, 2024 Sarah Parkes

We should start by appreciating that in reality many acid-base reactions are equilibrium reactions, even if it doesn’t appear obvious

Continue readingWhat are conjugate acid-base pairs?

Cat Links Physical chemistry

How to define an acid or a base?

Posted on April 26, 2022November 18, 2024 Sarah Parkes

At GCSE we defined acids as substances that ionised in water to give hydrogen ions, and an alkali dissolved in

Continue readingHow to define an acid or a base?

Cat Links Fundamentals

Ions and ionisation energies

Posted on April 25, 2022November 14, 2024 Sarah Parkes

An ion is an atom that has gained or lost electrons so that it is now charged – losing electrons

Continue readingIons and ionisation energies

Cat Links Exam question practice, Fundamentals, Physical chemistry

Atomic absorption and emission spectroscopy

Posted on April 25, 2022October 20, 2024 Sarah Parkes

How can we possibly know what elements are present in the stars? It’s not like we can nip off and

Continue readingAtomic absorption and emission spectroscopy

Cat Links Fundamentals

Nuclear fusion reactions

Posted on April 20, 2022October 2, 2024 Sarah Parkes

Have you ever wondered where the elements originally came from? I think it is time for a little stardust and

Continue readingNuclear fusion reactions

Cat Links Fundamentals

Atomic orbitals, sub-orbitals and electron configurations

Posted on April 20, 2022October 2, 2024 Sarah Parkes

At GCSE we learnt that electrons are arranged in shells or energy levels around a central nucleus – the first

Continue readingAtomic orbitals, sub-orbitals and electron configurations

Cat Links Fundamentals, Physical chemistry

Wavefunctions, quantum numbers and the atomic orbital

Posted on April 20, 2022October 2, 2024 Sarah Parkes

Wavefunctions and quantum numbers are the foundations of our current understanding of atomic structure, but this is advanced stuff, so

Continue readingWavefunctions, quantum numbers and the atomic orbital

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