Hydrogen (H)
element · nonmetal
Atomic number 1, mass 1.008. The simplest atom, and 90% of all atoms in the universe.
Encyclopedia
Written automatically as you experiment. Your discoveries appear at the top.
Carbon (C)
element · nonmetal
Atomic number 6, mass 12.011. Four bonding slots — the scaffolding of all known life.
Nitrogen (N)
element · nonmetal
Atomic number 7, mass 14.007. 78% of the air, and locked into every amino acid.
Oxygen (O)
element · nonmetal
Atomic number 8, mass 15.999. Greedy for electrons — which is exactly why it powers respiration.
Sodium (Na)
element · metal
Atomic number 11, mass 22.990. Gives away one electron eagerly — hence explosive in water.
Magnesium (Mg)
element · metal
Atomic number 12, mass 24.305. Sits at the heart of every chlorophyll molecule.
Phosphorus (P)
element · nonmetal
Atomic number 15, mass 30.974. The backbone of DNA and the 'P' in ATP.
Sulfur (S)
element · nonmetal
Atomic number 16, mass 32.06. Forms disulfide bridges that lock proteins into shape.
Chlorine (Cl)
element · halogen
Atomic number 17, mass 35.45. One electron short of stability, so it grabs hard.
Potassium (K)
element · metal
Atomic number 19, mass 39.098. Pumped across membranes to fire every nerve impulse.
Calcium (Ca)
element · metal
Atomic number 20, mass 40.078. Bone, shell, and the signal that makes muscles contract.
Iron (Fe)
element · transition
Atomic number 26, mass 55.845. Binds oxygen in haemoglobin, and rusts when it lets go.
Copper (Cu)
element · transition
Atomic number 29, mass 63.546. Conducts electrons brilliantly — in wires and in enzymes.
Zinc (Zn)
element · transition
Atomic number 30, mass 65.38. A structural pin inside hundreds of enzymes.
Water
biology · Simple molecules
The solvent everything else happens inside.
Glucose
biology · Simple molecules
Portable chemical energy, 6 carbons long.
Amino acid
biology · Building blocks
20 flavours, chained into every protein.
Fatty acid
biology · Building blocks
Water-hating tails that build membranes.
Nucleotide
biology · Building blocks
Sugar + phosphate + base: the letters of life.
Protein
biology · Machinery
Folded chains that catalyse, pump, and build.
Lipid bilayer
biology · Machinery
A self-assembling wall two molecules thick.
RNA
biology · Information
Message, machine, and possibly the first life.
DNA
biology · Information
A double-stranded archive with built-in backups.
ATP
biology · Energy
The rechargeable battery of every living cell.
Chloroplast
biology · Organelles
Turns photons into sugar.
Mitochondrion
biology · Organelles
Burns sugar into ATP, ex-bacterium.
Bacterial cell
biology · Organisms
The smallest complete living system.
Plant cell
biology · Organisms
A cell that eats light.