# Chemistry

**Type:** Topic
**Words:** 70

## About

Chemical substances, atomic structure, reactions, laboratory methods, and materials.

## Words by Level

### A2
- solution — A way of solving a problem or dealing with a difficult situation.; frequency rank 2412
- salt — A white substance used to add flavour to food and to preserve it.; frequency rank 2622
- product — Something that is made or grown to be sold.; frequency rank 3149
- chemical — A substance, such as an element or compound, used in or produced by chemistry.; frequency rank 4179
- atom — The smallest part of a chemical element that can exist.; frequency rank 9239

### B1
- iron — A common hard grey metal that rusts and is used to make steel; frequency rank 2196
- alcohol — Drinks such as beer, wine, and spirits that can make you drunk.; frequency rank 2558
- reaction — The way you behave or feel because of something that has happened.; frequency rank 2912
- oxygen — A colourless, odourless gas that humans and animals need to breathe and that makes up part of the air.; frequency rank 3536
- element — One of the parts that together make up a whole.; frequency rank 5109
- chemistry — The science that studies what substances are made of and how they change.; frequency rank 5497
- compound — a substance made by combining two or more elements or ingredients; frequency rank 5840
- laboratory — A room or building equipped for scientific research, experiments, or analysis.; frequency rank 6012
- organic — Grown or produced without artificial chemicals, fertilizers, or pesticides.; frequency rank 6250
- concentration — the ability to give all your attention to something; frequency rank 6525
- atomic — Relating to atoms, the tiny units that make up all matter.; frequency rank 7275
- chemist — A scientist who studies or works with chemistry.; frequency rank 11431
- molecular — relating to or produced by or consisting of molecules; frequency rank 12289
- sodium — Employing sodium.; frequency rank 12395
- dioxide — A chemical compound that has two oxygen atoms in each molecule.; frequency rank 12561
- nitrogen — The chemical element with an atomic number of 7 and atomic weight of 14.0067. It is a colorless and odorless gas.; frequency rank 12923
- dissolve — To mix into a liquid and become part of it.; frequency rank 13434
- reduction — The act of making something smaller or less.; frequency rank 14282
- calcium — the chemical element with symbol Ca and atomic number 20, a soft, silvery, reactive alkaline-earth metal that occurs naturally only in compounds; frequency rank 14517
- nucleus — The central part of an atom, made of protons and neutrons.; frequency rank 16440
- electron — A tiny particle inside an atom that carries a negative electric charge.; frequency rank 17165
- molecule — The smallest unit of a substance that still has all its chemical properties, made of two or more atoms joined together.; frequency rank 18594
- oxide — a chemical compound of oxygen with another element; frequency rank 21137
- chloride — the negatively charged chlorine ion, Cl−, found in many salts and serving as an important electrolyte in body fluids; frequency rank 23978
- inorganic — relating or belonging to the class of compounds not having a carbon basis; frequency rank 45306

### B2
- acid — A chemical substance, often sour or corrosive, that reacts with bases and can dissolve metals.; frequency rank 4651
- copper — A soft reddish-brown metal (symbol Cu) used in wires, pipes, and coins.; frequency rank 5308
- carbon — A chemical element (symbol C) found in all living things, and in forms such as graphite and diamond.; frequency rank 5799
- protein — A nutrient found in foods such as meat, eggs, and beans that the body needs to grow and stay healthy.; frequency rank 7714
- potassium — the chemical element with symbol K and atomic number 19, a soft, silvery, highly reactive alkali metal that occurs naturally only in compounds; frequency rank 14816
- ion — an atom or group of atoms with a positive or negative electrical charge because it has lost or gained electrons; frequency rank 16977
- sulfur — A bright yellow chemical element (symbol S) with a strong smell, used in matches, gunpowder, and many industrial products.; frequency rank 17888
- neutron — an elementary particle with 0 charge and mass about equal to a proton; frequency rank 18928
- catalyst — Something or someone that causes an important change or event to happen.; frequency rank 21475
- enzyme — a protein or RNA molecule that catalyzes a biochemical reaction without being consumed by it; frequency rank 21762
- magnesium — the chemical element with atomic number 12, a light, silvery-white metal that burns with an intense white flame; frequency rank 22415
- proton — A positively charged subatomic particle forming part of the nucleus of an atom and determining the atomic number of an element, composed of two up quarks and a down quark.; frequency rank 23694
- solvent — A liquid that can dissolve other substances.; frequency rank 26875
- beaker — a straight-sided, flat-bottomed laboratory container, usually with a pouring lip; frequency rank 28552
- evaporation — the process by which a liquid changes into a gas, especially at its surface; frequency rank 43309

### C1
- crystal — A clear, solid mineral form with a regular geometric shape; high-quality clear glass.; frequency rank 3079
- hydrogen — The lightest chemical element (symbol H), a colorless, odorless, highly flammable gas.; frequency rank 8914
- flask — A small flat bottle for carrying a drink, often kept in a pocket.; frequency rank 15136
- chlorine — the chemical element with atomic number 17, a toxic greenish-yellow halogen gas in its elemental form; frequency rank 19616
- saturation — the state or process of being completely soaked, filled, or supplied to capacity; frequency rank 31230
- acidic — Containing acid, or having a pH lower than 7.; frequency rank 33374
- soluble — susceptible of solution or of being solved or explained; frequency rank 59903
- insoluble — without hope of solution; frequency rank 72254
- polymer — a large molecule made of many repeating smaller units linked together, or a material consisting of such molecules

### C2
- combustion — The process of burning, in which a substance reacts with oxygen to produce heat and light.; frequency rank 20444
- nitrate — a salt or ester of nitric acid, containing the nitrate ion or nitrate group; frequency rank 21362
- equilibrium — A state of balance in which opposing forces or influences cancel each other out.; frequency rank 23040
- isotope — one of two or more atoms with the same atomic number but with different numbers of neutrons; frequency rank 32882
- sulfate — Any salt or ester of sulfuric acid.; frequency rank 39470
- alkaline — relating to or containing an alkali; frequency rank 46473
- distillation — The process of purifying a liquid by boiling it and condensing the vapor.; frequency rank 58799
- reagent — a substance or mixture used to cause, detect, measure, or investigate a chemical reaction; frequency rank 60412
- electrolysis — The chemical change produced by passing an electric current through a conducting solution or a molten salt.; frequency rank 62346
- crystallization — The process of becoming clear, definite, or precise.; frequency rank 79779
- pipette — a narrow graduated tube used to measure or transfer a small quantity of liquid; frequency rank 89353
- chromatography — a method of separating the components of a mixture by their different movement through a stationary material as a fluid passes over or through it

### C2+
- corrosion — The gradual destruction or undermining of something.; frequency rank 40330
- precipitate — to cause to happen suddenly; hasty; a solid separated from a solution
- precipitation — rain, snow, or other water falling from the sky; hasty action
- alkali — a soluble base that neutralizes acids, turning litmus blue