Chemistry · Physics · 52 charts · 33 chart types
Chemistry and physics basics
School science, one chart at a time. What the elements are and why the table that lists them repeats, what a body and a planet are made of, how water melts and boils, why a thrown ball follows a curve, how waves add up, and what holds a planet in its orbit. Each idea gets the chart type that shows it best.
This page is a tour of Holochart's chart types more than a science course: every idea is kept to what a school textbook covers, and every chart is a Holochart example that runs live in your browser and doubles as a visual regression test. Drag the 3D charts to turn them, hover for the numbers, and use the toggles above a chart to switch what it shows. Where a chart uses simulated measurements, its title says so.
The elements
The periodic table: 18 columns (groups), 7 rows (periods), and the lanthanides and actinides in two rows below. Switch the coloring to see electronegativity peak at fluorine (3.98), melting point at tungsten (3,695 K) and density at osmium (22.6 g/cm³).
Why it is called periodic
The energy needed to pull one electron off an atom, element by element. It peaks at each noble gas (helium, 24.6 eV) and drops at each alkali metal (caesium, 3.9 eV), and the same zigzag repeats in every row. That repetition is the "period" in the table's name.
Density, across the table
The same table lying flat, with each bar as tall as the element's density. The metals in the middle of period 6 tower over the rest, led by osmium at 22.57 g/cm³; the gases barely rise off the floor.
Density again, by family. The alkali metals have a median of about 1 g/cm³ (lithium, at 0.53, floats on water); the transition metals about 10 g/cm³.
Families
The family tree of the elements: 91 metals, 7 metalloids and 20 nonmetals, split into ten categories. The transition metals are the biggest family, with 38 elements. Click a ring to zoom in.
All 118 elements sorted by kind, category and state at room temperature: 104 are solid, 12 are gases and only 2 are liquid, mercury and bromine.
Melting and boiling
Elements that are hard to melt are also hard to boil. Tungsten melts at 3,695 K; helium boils at 4 K. Bigger bubbles are denser elements.
Each bar runs from the melting point to the boiling point, the temperatures at which the element is a liquid. Only bromine (266 to 332 K) and mercury (234 to 630 K) cross the room temperature line at 293 K.
Four properties at once
Atomic mass, radius, electronegativity and ionization energy of 91 elements, each plotted against each. The tightest link is between the last two: atoms that hold their own electrons tightly also pull hard on shared ones.
When they were found
Eleven elements, such as gold, copper, iron and carbon, have been known since antiquity. The other 107 were found after 1650, with the busiest stretches in 1800 to 1825 (18 elements) and 1875 to 1900 (19 elements).
What things are made of
Oxygen is the biggest part of your body (65% by mass) and of the ground (46.1%), and a fifth of the air (20.95% by volume). Each element keeps its color in all three donuts.
The Earth's crust, with each tile's area the element's share by mass. Oxygen and silicon make up three quarters; all the metals together are about a quarter.
The Sun is 73.5% hydrogen and 24.9% helium by mass. Everything else fits in the tip.
Sorting matter
All matter is either a pure substance (an element or a compound) or a mixture (the same throughout, or with parts you can see).
Atoms and molecules
The shell model of an atom: sodium has 11 electrons, 2 in the first shell, 8 in the second and 1 alone in the third. It is a way to count electrons, not a picture of where they are.
Where the electron really is
20,000 simulated positions of hydrogen's one electron. The cloud is densest at the nucleus and fades outward.
An orbital is a map of where the electron is likely to be: it is inside each surface 90% of the time. The first is a ball, the next a dumbbell, then a dumbbell with a ring.
The shapes of molecules
Water is bent (104.5° between its two bonds), carbon dioxide is a straight line, ammonia a low pyramid (107°) and methane a tetrahedron (109.5°).
Methane's four hydrogens sit at the corners of a tetrahedron, which is as far apart as four bonds can get.
Fingerprints in light
A glowing gas gives off only certain wavelengths. Hydrogen shows four visible lines; sodium's two yellow lines, at 589.0 and 589.6 nm, are too close to tell apart here.
Heat, gases and change
Heating 1 kg of ice from −20 °C to steam at 120 °C. The temperature stands still while the ice melts (334 kJ) and while the water boils (2,260 kJ, over five times what it takes to heat the water from 0 to 100 °C).
Which state water is in at each temperature and pressure. At normal air pressure it melts at 0 °C and boils at 100 °C; all three states meet at the triple point.
One temperature on three scales. Absolute zero is 0 K, −273.15 °C or −459.67 °F.
Molecules in a gas
Simulated speeds of 4,000 nitrogen molecules at each temperature, with the theoretical curve on top. Hotter gas is faster and more spread out: the mean is 275 m/s at 100 K and 825 m/s at 900 K.
Six gases at the same temperature. Lighter molecules move faster: hydrogen averages 1,782 m/s, carbon dioxide 380 m/s.
The pressure of a fixed amount of gas for every volume and temperature: it rises in a straight line as you heat it and ever more steeply as you squeeze it.
Particles taking random steps from the center. A hundred times longer spreads the cloud only ten times wider.
Acids and bases
From battery acid (pH 1) to drain cleaner (pH 14), with pure water at 7. Each step is a factor of ten.
Adding a base to an acid drop by drop. The pH creeps up, then jumps through 7 at exactly 25 mL, crossing both indicators' color changes within a drop.
Energy in a reaction
Burning methane costs 2,648 kJ per mole to break the old bonds and gives back 3,450 kJ when the new ones form. The difference, 802 kJ, comes out as heat.
Radioactive decay
Every 5,730 years half of the remaining carbon-14 is gone.
The same decay as a smooth curve. The carbon-14 that disappears turns into nitrogen-14, so the two always add up to 100%.
Motion and energy
A ball thrown at 20 m/s with no air resistance. 45° goes farthest (40.8 m); 30° and 60° land on the same spot.
A ball thrown straight up at 15 m/s. Its velocity falls steadily through zero at the top; the acceleration is the same −9.81 m/s² all the way.
Two school experiments
Simulated readings of a spring loaded with 50 to 500 g: the stretch is proportional to the force, and the slope of the line gives the spring constant.
Twelve simulated stopwatch readings at each of five pendulum lengths. Four times the length gives twice the period.
Energy changes form
Press Play: as the pendulum swings, its energy moves between height and motion while the total stays the same.
Of every 100 units of energy in a car's fuel, about 62 leave as engine heat and only 18 reach the wheels (typical, rounded values).
Waves and light
Where two waves meet, their heights add. In step they make a wave twice as tall; half a wavelength out of step they cancel.
Ripples from two sources. Where crests meet the water rises twice as high; along the dark bands a crest always meets a trough and the water stays flat.
Radio waves, microwaves, infrared, light, ultraviolet, X-rays and gamma rays are the same kind of wave at different wavelengths. Everything we can see fits between 380 and 750 nm.
Light spreads over a bigger sphere the farther it travels, so twice as far from a lamp it is a quarter as bright.
Two polarizing filters, like two pairs of sunglasses: lined up they let the light through, crossed at 90° they block it.
Electricity and magnetism
For a resistor, doubling the voltage doubles the current. A filament lamp bends away from the straight line because its resistance grows as it heats up.
The electric potential around a positive and a negative charge: high near the plus, low near the minus, and exactly zero halfway between.
The field around the same two charges in 3D. Each cone points the way a small positive charge would be pushed.
Field lines of a bar magnet leave the north pole, loop round and come back in at the south pole.
The planets
The eight planets from the Sun outwards.
Each line is a planet. The four rocky planets run together (small, dense, close to the Sun), and so do the four giants (large, light, far and cold).
Orbits
Orbits are ellipses with the Sun off-center. Venus and the Earth are almost circles; Mercury and Mars are visibly lopsided.
The farther a planet is from the Sun, the longer its year, and the rule is exact: four times as far means eight times as long.
Gravity
Your mass is the same everywhere, but your weight is mass times gravity. A 50 kg person weighs 490 N on Earth, 185 N on Mars and 1,155 N on Jupiter.
Sources
Element data: the PubChem periodic table (US National Library of Medicine, public domain), with three discovery years corrected. Planets: NASA Planetary Fact Sheet. Everything else is computed from textbook formulas and constants; measurements described as simulated are generated with a fixed random seed. Details: SOURCES.md. Chart sources: examples/demos/science-basics.