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Category: Physical chemistry

Cat Links Calculations, Physical chemistry

What is a buffer and how do I calculate its pH?

Posted on April 28, 2022September 2, 2025 Sarah Parkes

A buffer is defined as a solution that is able to resist changes in pH when small amounts of acid

Continue readingWhat is a buffer and how do I calculate its pH?

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 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, 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

Cat Links Calculations, Exam question practice, Physical chemistry

Why are ionic compounds soluble? (part 2)

Posted on April 19, 2022August 27, 2025 Sarah Parkes

For a full understanding of why ionic compounds are soluble we need to consider both the enthalpy and entropy changes

Continue readingWhy are ionic compounds soluble? (part 2)

Cat Links Physical chemistry

A quick note on solvents

Posted on April 19, 2022October 2, 2024 Sarah Parkes

This seems just the right moment to refresh your understanding of the different types off solvent so that you can

Continue readingA quick note on solvents

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