Moleculars

Содержание и основные понятия

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Alterna · physics · 1.1
Moleculars
The building of the substance, the molecules and the atoms, the size of the particles.
If you zoom in an apple to the size of the Earth, the apple molecule will be the same size as an a Apple, and everything around it is made up of invisible particles -- and it's not a guess, but a proven fact.
GEF · Grade 7
PIF · Baseline
01
Building the substance
What are all the bodies around us made of?
A hypothesis of a discrete substance structure
Ancient Greek philosophers (Democrit, ~400 B.C.E.) assumed that the substance
Not complete
and consists of the smallest particles,
Atoms
The word "atom" means "uneven".
Modern physics has confirmed that all bodies are made up of particles.
Spaces
.
Evidence: compression of substances
Why can the air be compressed and the water almost non-existent? Because between gas particles there are large intervals and between liquid particles there is small ones. Congestion means reducing the gaps, not the particles themselves.
Experience: drop of oil on water
If a drop of 1 mm3 of oil is spilled onto the surface of the water, it flows into a spot of ~1 m2. The thickness of the oil layer is ~0.000001 mm. This is the size of one oil molecule.
02
Moleculars and Atoms
Smallest particles of matter
Molecula
Molecula
The molecule of H2O water consists of 3 atoms (2 hydrogen + 1 oxygen) and the oxygen molecule O2 consists of 2 atom.
Atom
Atoms connect to molecules.
Dimensions of molecules
The size of the molecule is about
10 - 10 m
(0.000000001 m, or 0.1 nanometra). 1 cm3 of air contains ~2.7×1019 molecules. If each molecule was increased to the size of the grain, the air would fill the entire globe.
That's curious.
The protein molecule can contain millions of atoms, and some substances (metals, inert gases) do not form molecules — their atom is located as a crystal grate or separate.
🪲
Molecular Model — Phase Transition
IV-005 · Move the temperature and watch the transition
Temperature:
300
K
C
What needs to be understood
Outcome 1
Explain the physical meaning of the topic "Molecules" through the model, not just the formula.
Outcome 2
To distinguish and correctly use terms: molecule, atom, particle size.
Outcome 3
Indicate the conditions for the applicability of the law, verify units and limit cases.
T
Terms of the topic
The definition should indicate the physical meaning, not a substitute for a domestic synonym.
molecule
The lowest electrically neutral particle of a substance that preserves its chemical properties.
Atom
Electrically neutral system made of positive kernel and electronic envelope.
Particle size
The characteristic linear scale of the particle, depending on the physical model chosen and the measurement method chosen.
Inter-molecular interaction
Pushing and pushing between molecules depending on distance and mutual orientation.
F
Origin and conclusion of the formulas
The fundamental law cannot be "proven" by algebras: for each record, it is stated whether it is a definition, an experimental law, or a model effect.
Qualitative theme
The main content of this topic is expressed by models, observations and causal relationships; the formula is not artificially added: quantitative laws are introduced on connected pages.
!
Model boundaries and typical errors
Error: Forget model condition
You can't change the formula to any situation just because it's a coincidence of letters. The key condition of this topic is that if you zoom in on an apple to the size of the Earth, the apple molecule is the size that it is. Everything around it is made up of invisible particles -- and that's not a guess, but a proven fact.
How to Check the Mind
The formula is only applicable after selecting the system and assumptions. Then check the unit, vector direction and result behaviour at zero or very large parameter.
Σ
Conclusion on the topic
Moleculars
If you zoom in an apple to the size of the Earth, the apple molecule will be the same size as an a Apple, and everything around it is made up of invisible particles -- and it's not a guess, but a proven fact.
If you zoom in an apple to the size of the Earth, the apple molecule will be the same size as an a Apple, and everything around it is made up of invisible particles -- and it's not a guess, but a proven fact.
The formula is applicable only after the selection of the system and assumptions.
Any numerical result shall be accompanied by a unit, a sign and an explanation of its physical meaning.
The content is consistent with the FRP on Physics of the OS/OSS 2025 and the subject matter of the current lines of the PNP: I. M. Peryškin and co-authors (7–9), G. J. Mäkishev and coauthors (10–11), and with the lines "Engineers of the Future" and V. A. Kasyanov. The original texts are not reproduced, the text of the textbooks is not reproduced.