Bunsen Bites — small bites, big discoveries

We're tracking down missing metal. First we find out where it disappears to in acid. Then we catch metal doing the opposite in plain air, getting heavier, and work out what it stole.

The case is solved: metal is never lost or created, it just swaps partners. You can now say both word equations, name the salt from the acid, describe the pop test, and explain why a dry iron nail doesn't rust.

Sources:

• https://www.savemyexams.com/gcse/chemistry/aqa/18/revision-notes/8-chemical-analysis/8-2-identification-of-common-gases/8-2-1-test-for-hydrogen/
• https://edumentors.co.uk/blog/test-for-hydrogen-gcse-chemistry/
• https://senecalearning.com/en-gb/revision-notes/ks3/science/science-ks3/2-8-1-testing-for-gases
• https://www.lemonade-ed.com/year-9/material-world/gas-tests
• https://digitalteachers.co.ug/wp-content/uploads/2025/12/Rusting-of-iron.pdf
• https://www.fizzicseducation.com.au/150-science-experiments/kitchen-chemistry-experiments/rusty-nail-experiment/
• https://en.wikipedia.org/wiki/Tarnish

Source: Episode 11 - Chemistry Level 8, Chapter 4: Metals and other materials (1/4). Metal reactions (4.1-4.2), about…
Sections: 4.1, 4.2
Style: Exam prep
Length: 1009 words, 6 min target
Generated: 2026-10-25

Here's the secret behind every way of pulling a mixture apart: find the one way its bits are different, then turn that difference into a race only some of them can win. We'll start with the most beautiful race in chemistry, paper chromatography, then go back to your kitchen, where you've been running these races for years without knowing it.

Back to the tea bag: it's a race where the leaves are disqualified at the gate. The listener can now look at any mixture and ask the one question that matters: what's different about these bits, and how do I race on it? And they can state that Rf is the substance's distance divided by the solvent front's distance, with no units.

Sources:

• https://en.wikipedia.org/wiki/Paper_chromatography

Source: Episode 10 - Chemistry Level 8, Chapter 3: Separation techniques (4/4). Chromatography and everyday…
Sections: 3.7, 3.8
Style: Exam prep
Length: 1013 words, 6 min target
Generated: 2026-10-25

We're going to chase that question. First we'll see what a filter can actually catch, then why salt slips straight through it, and what you have to do instead.

The sieve couldn't tell salt from water, but boiling can. With that, the listener can rescue either half of salt water: evaporate to keep the salt, distil to keep the water. They can also explain why a filter alone never could.

Source: Episode 9 - Chemistry Level 8, Chapter 3: Separation techniques (3/4). Filtration, evaporation and…
Sections: 3.5, 3.6
Style: Exam prep
Length: 1242 words, 7 min target
Generated: 2026-10-25

In the next few minutes we're going to track that sugar down. First we prove it never actually left. Then we find out that water can only hide so much, and what happens when it runs out of room.

The crystals that appear on cooling are the hidden stuff coming back, and that answers both opening questions. It never left, because mass is conserved, and you get it back by shrinking the water's hiding room, which means cooling it. Even a saturated solution that looks still is busy, with particles dissolving and re-forming crystals at exactly the same rate. The listener can now state the quantity: solubility is grams of solute per 100 g of water at a given temperature.

Sources:

• https://www.creative-chemistry.org.uk/documents/N-m21-04.pdf
• https://www.cliffsnotes.com/study-notes/33679916
• https://www.chemguide.co.uk/physical/phaseeqia/saltsoln.html

Source: Episode 8 - Chemistry Level 8, Chapter 3: Separation techniques (2/4). Dissolving (3.3-3.4), about 5-6 min
Sections: 3.3, 3.4
Style: Exam prep
Length: 1063 words, 6 min target
Generated: 2026-10-25

So we're going to find out what 'pure' really means to a chemist, and why the juice fails the test. Then we'll see what the juice actually is, and why that turns out to be useful rather than a let-down.

The listener can now catch the word 'pure' lying. Pure means one substance, and you can check it because the substance melts sharply at one fixed temperature. Anything else is a mixture, where the parts keep their own properties, come in any amounts and can be pulled apart. That ability to pull things apart is what the next three episodes are about.

Sources:

• https://www.thenational.academy/teachers/programmes/chemistry-secondary-ks4-higher-ocr/units/states-of-matter/lessons/pure-substance
• https://www.vaia.com/en-us/textbooks/chemistry/introductory-chemistry-a-foundation-7-edition/chapter-3/problem-7-why-would-a-chemist-find-fault-with-the-phrase-pur/
• https://chem.libretexts.org/Courses/Harper_College/CHM_110:_Fundamentals_of_Chemistry/01:_The_Process_of_Science/1.07:_Classifying_Matter_According_to_Its_Composition
• https://www.science-revision.co.uk/purity%20and%20formulation.html
• https://yesdirt.com/is-orange-juice-a-pure-substance/
• http://hyperphysics.phy-astr.gsu.edu/hbase/Chemical/meltpt.html
• https://en.wikipedia.org/wiki/Freezing-point_depression
• https://www.lpi.usra.edu/education/explore/ice/background/allAboutWater/
• https://www.scientificamerican.com/article/why-do-we-put-salt-on-icy/
• https://en.wikipedia.org/wiki/Atmosphere_of_Earth
• https://en.wikipedia.org/wiki/Seawater
• https://rwu.pressbooks.pub/webboceanography/chapter/5-3-salinity-patterns/

Source: Episode 7 - Chemistry Level 8, Chapter 3: Separation techniques (1/4). Pure substances and mixtures…
Sections: 3.1, 3.2
Style: Exam prep
Length: 1046 words, 6 min target
Generated: 2026-10-25

The answer is the difference between atoms that are just hanging around together and atoms that are actually locked together. Once you get that difference, you can read a chemical formula, and you'll see how a deadly gas and a dangerous metal end up on your chips.

The listener can now answer the opening question. You can't breathe the oxygen in water because it isn't oxygen gas any more. It is bonded into a new substance, and the formula H₂O tells you exactly how. The same idea explains salt. The episode ends with three plain sentences the listener can repeat: element means one kind of atom, compound means different atoms bonded in a fixed recipe, and mixture means things together but not joined, like the air you've been breathing the whole time.

Sources:

• https://www.chemicool.com/elements/composition-of-air.html
• https://homework.study.com/explanation/air-contains-mostly-nitrogen-78-and-oxygen-21-it-also-contains-other-gases-including-carbon-dioxide-and-helium-and-various-pollutants-both-gases-and-solids-give-a-brief-explanation-about-why-air-is-a-mixture-whether-it-is-homogenous-or-heteroge.html
• https://chem.libretexts.org/Courses/Anoka-Ramsey_Community_College/Introduction_to_Chemistry/16:_Environmental_Chemistry/16.03:_The_Air_We_Breathe
• https://chem.libretexts.org/Bookshelves/Introductory_Chemistry/Chemistry_for_Changing_Times_(Hill_and_McCreary)/04:_Chemical_Bonds/4.03:_The_Reaction_of_Sodium_with_Chlorine

Source: Chemistry Level 8, Chapter 2: Atoms and the Periodic Table (3/4)
Sections: 2.5
Style: Exam prep
Length: 878 words, 5 min target
Generated: 2026-10-24

So we're chasing one question: what does an atom actually want? First we'll work out exactly what 'full' means for an atom. Then we'll find the two ways atoms get there: one grabs, one shares.

The listener can now predict the bond without memorising a list. Is it a metal meeting a non-metal? Something gets handed over and ions form. Two non-metals? They share and a molecule forms. Both follow from the 2,8,8 rule they learned in the first half.

Sources:

• https://brainly.com/question/29564215
• https://en.wikipedia.org/wiki/Noble_gas

Source: Chemistry Level 8, Chapter 2: Atoms and the Periodic Table (4/4)
Sections: 2.6, 2.7
Style: Exam prep
Length: 1205 words, 8 min target
Generated: 2026-10-24

We're going to find out what sodium and chlorine actually are, why one counts as a metal and the other doesn't. Then we'll see why those two in particular grab each other so hard, and why some elements refuse to grab anything at all.

Back to the salt shaker. It holds one element from the metal side and one from the non-metal side, a Group 1 metal and a Group 7 halogen, and they've cancelled each other's danger out. The listener can now say what makes something a metal, where the line is, and which way reactivity runs in Groups 1, 7 and 0.

Source: Chemistry Level 8, Chapter 2: Atoms and the Periodic Table (2/4)
Sections: 2.3, 2.4
Style: Exam prep
Length: 994 words, 6 min target
Generated: 2026-10-24

So how do you describe something before it exists? We'll follow Mendeleev's trick first, then crack open an atom and find that the clue he was sorting by wasn't what really makes an element itself.

Gallium's real address isn't 'weighs about 68'. It's 'has 31 protons'. The listener can now say what atomic number is (number of protons) and what mass number is (protons + neutrons, a plain count with no units). They can also say why the table is really built on the first one.

Sources:

• https://en.wikipedia.org/wiki/Gallium
• https://www.reagent.co.uk/blog/paul-emile-lecoq-de-boisbaudran/
• https://periodic-table.rsc.org/element/31/gallium

Source: Chemistry Level 8, Chapter 2: Atoms and the Periodic Table (1/4)
Sections: 2.1, 2.2
Style: Exam prep
Length: 1041 words, 6 min target
Generated: 2026-10-24

We're going to track down the invisible thing that was shoving that pollen around. Then we'll use it to solve a harder case: two liquids that look exactly the same. How do you prove which is which?

The mystery Brown couldn't solve becomes a tool. The same particle picture that explains the dancing pollen lets the listener name a substance by its fingerprint. They can say what density is (mass ÷ volume, in g/cm³) and why a gas is far less dense than a liquid of the same stuff.

Sources:

• https://www.eurekalert.org/news-releases/611119

Source: Chemistry Level 8, Chapter 1: The particle model and state change (1/2)
Sections: 1.1, 1.2, 1.3
Style: Exam prep
Length: 1452 words, 8 min target
Generated: 2026-10-24