2025.12.25
Why do acids and bases "neutralize"? An ion relay in water
The acid-base reaction is not simply the two liquids canceling each other out, but the result of the recombination of hydrogen ions and hydroxide ions.
Views 18,009Comments 7
CHEMISTRY NOTES
Chemistry Notes
2025.09.30
Why does iron rust? Oxidation-reduction reactions are hidden in every layer of rust spots
Rusting is not the unilateral "oxidation" of iron, but a set of electrochemical processes involving electron transfer, water film and oxygen.
Views 8,607Comments 10
2025.01.07
A glass of clear water suddenly turns turbid: how precipitation reaction turns ions into solid
When a white or yellow solid appears after mixing two clear solutions, the ions in the solution are crossing some solubility boundary.
Views 3,549Comments 5
2023.05.12
A catalyst is not a "speed button": it just changes the path for a reaction
The catalyst is not consumed by the reaction, but can significantly change the reaction speed. The key is to reduce the energy barrier through which the reaction passes.
Views 10,127Comments 7
2024.03.05
How does plastic “grow”? Molecular Solitaire from Monomer to Polymer
Behind a plastic fiber, a transparent bottle and a soft film may be long chains of small molecules that are continuously connected.
Views 3,745Comments 7
2025.07.20
Why do chemical reactions change color? Electrons jump one step between different energy levels
Changes in the color of the solution often indicate changes in the molecular structure, oxidation state or coordination environment.
Views 14,775Comments 7
2026.01.03
How does soap remove oil? A chemical reaction that makes oil and water shake hands
The cleaning power of soap comes from the two ends of the molecules: one end likes water, the other end likes oil, and finally the oil is encapsulated in micelles.
Views 17,360Comments 8
2021.12.11
Why can batteries generate electricity? Chemical energy turns into electric current along electron channels
The battery does not create electrons out of thin air, but allows oxidation and reduction reactions to occur at two electrodes respectively, and forces the electrons to pass through an external circuit.
Views 13,760Comments 5
2023.08.09
What happened in the flames? Combustion is a rapid exchange of electrons
Combustion is not just "lighting up when encountering oxygen", but a chemical process in which combustibles are oxidized and energy is concentrated and released.
Views 13,037Comments 8
2025.11.29
Why didn't the reaction go through to the end? Chemical equilibrium is actually constantly changing dynamically
In a seemingly static equilibrium system, reactions in both forward and reverse directions are still happening at the same time, but at exactly the same rate.
Views 8,049Comments 5
2021.11.16
Why can gas be compressed? The space between molecules is actually beyond imagination
The volume of a gas comes primarily from the space in which the molecules move, rather than the size of the molecules themselves.
Views 8,970Comments 10
2023.12.19
Crystals don't 'grow' from stone: How molecules line up in neat rows
The shape of a crystal records how the particles are arranged and also records the history of temperature, concentration and growth rate.
Views 4,235Comments 7
2024.09.21
Why can't blood alternate between acid and alkaline? Buffer solutions hold the pH line
The buffer system can absorb the impact of a small amount of acid or alkali, keeping the pH of the solution relatively stable.
Views 11,017Comments 9
2026.01.25
Why do enzymes make reactions hundreds of millions of times faster? Precise reaction sites hidden on protein surfaces
Enzymes are highly selective catalysts in living systems, using their shape and local chemical environment to identify target molecules.
Views 16,206Comments 5
2026.04.08
Where does the scent come from? What your nose smells is a group of volatile molecules
Floral, fruity and baked aromas are not abstract sensations but the result of the interaction of volatile molecules with olfactory receptors.
Views 17,264Comments 9
2026.05.31
Is the bleach "washing out the color"? It actually changes the structure of the colored molecules
Bleaching usually does not remove color, but destroys the structures in molecules responsible for absorbing visible light.
Views 16,948Comments 7
2025.12.01
Why is glass transparent and hard? It is a solid with no long-range order
Glass is not as neatly arranged as crystals, but it can obtain unique optical and mechanical properties through its amorphous structure.
Views 11,341Comments 8
2025.06.24
Light can also drive chemical reactions: electrons on the surface of semiconductors are awakened by sunlight
Photocatalytic materials absorb photons to generate electrons and holes, which can further participate in redox reactions.
Views 11,726Comments 10