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acid

a chemical substance with a pH below 7 that can dissolve metals and turn litmus paper red.

Noun chemical_compound Level 314

ammonia

A pungent, colorless gas (NH₃) composed of nitrogen and hydrogen, widely used in fertilizers, cleaning products, and industrial chemistry.

Noun chemical_compound Level 314

base

a chemical substance with a pH above 7 that can neutralize acids and turn litmus paper blue.

Noun chemical_compound Level 314

carbon

A chemical element with atomic number 6, occurring in all known living organisms and in forms such as diamond, graphite, and charcoal.

Noun chemical_compound Level 314

carbon dioxide

A colorless gas (CO₂) produced by burning carbon and organic compounds and by respiration, absorbed by plants in photosynthesis.

Noun chemical_compound Level 314

carbonate

A salt or ester of carbonic acid, containing the carbonate ion CO₃²⁻.

Noun chemical_compound Level 314

chloride

A chemical compound containing chlorine combined with another element or group, especially a salt in which chlorine exists as the negatively charged i...

Noun chemical_compound Level 314

chlorine

A chemical element (symbol Cl) that is a yellow-green, toxic gas with a pungent smell, commonly used to disinfect water and in manufacturing.

Noun chemical_compound Level 314

hydrogen

The lightest and most abundant chemical element (symbol H), a colorless, odorless gas that combines with oxygen to form water.

Noun chemical_compound Level 314

methane

A colorless, odorless, flammable gas (CH₄) that is the main component of natural gas and a significant greenhouse gas.

Noun chemical_compound Level 314

nitrogen

A chemical element (symbol N) that is a colorless, odorless gas making up about 78% of Earth's atmosphere, essential for plant growth.

Noun chemical_compound Level 314

oxygen

A chemical element (symbol O) essential for respiration, making up about 21% of Earth's atmosphere.

Noun chemical_compound Level 314

sodium

A soft, highly reactive chemical element with the symbol Na and atomic number 11, commonly found in compounds such as salt.

Noun chemical_compound Level 314

collagen

A tough, fibrous protein that forms the main structural component of connective tissues such as skin, bones, cartilage, tendons, and ligaments.

Noun chemical_compound Level 1010

propellant

A substance used to produce thrust or pressure, especially to propel a rocket, projectile, or other object.

Noun chemical_compound Level 1040

acetone

A colorless, highly flammable liquid ketone used as a solvent, especially in products such as nail-polish remover, and as an industrial chemical.

Noun chemical_compound Level 1050

ammonium

A positively charged polyatomic ion, NH₄⁺, formed when ammonia accepts a proton; it occurs in many salts and behaves chemically somewhat like an alkal...

Noun chemical_compound Level 1050

anion

An ion with a negative electrical charge, formed when an atom or molecule gains one or more electrons.

Noun chemical_compound Level 1050

benzene

A colorless, highly flammable liquid aromatic hydrocarbon with the chemical formula C₆H₆, used as an industrial solvent and in manufacturing; it is to...

Noun chemical_compound Level 1050

bicarbonate

A salt containing the bicarbonate ion (HCO₃⁻), especially sodium bicarbonate, commonly known as baking soda.

Noun chemical_compound Level 1050

catalyst

A substance that increases the rate of a chemical reaction without being consumed or permanently changed.

Noun chemical_compound Level 1050

chlorophyll

A green pigment in plants, algae, and some bacteria that absorbs light energy for photosynthesis.

Noun chemical_compound Level 1050

compound

A substance formed when two or more chemical elements combine in fixed proportions.

Noun chemical_compound Level 1050

cyanide

A highly poisonous chemical compound containing the cyanide ion (CN−), commonly referring to hydrogen cyanide or a cyanide salt.

Noun chemical_compound Level 1050

dioxide

A chemical compound containing two oxygen atoms combined with one atom of another element.

Noun chemical_compound Level 1050

ethylene

A colorless, flammable hydrocarbon gas with the chemical formula C₂H₄, used industrially to make plastics and other chemicals and naturally produced b...

Noun chemical_compound Level 1050

fluoride

A chemical compound containing fluorine, especially a salt of hydrofluoric acid; commonly added to toothpaste or drinking water to help prevent tooth ...

Noun chemical_compound Level 1050

formaldehyde

A colorless, strong-smelling, highly reactive gas used in manufacturing resins, plastics, textiles, and disinfectants, and commonly encountered in dil...

Noun chemical_compound Level 1050

fructose

A simple sugar found naturally in fruits, honey, and some vegetables; it has the same chemical formula as glucose but a different molecular structure.

Noun chemical_compound Level 1050

hydrolysis

A chemical reaction in which a compound is broken down by reacting with water, often producing new substances from the compound’s components.

Noun chemical_compound Level 1050

hydroxide

A chemical compound containing one or more hydroxyl groups, especially a compound formed when a metal or positive ion combines with the hydroxide ion ...

Noun chemical_compound Level 1050

isotope

One of two or more atoms of the same chemical element that have the same number of protons but different numbers of neutrons, and therefore different ...

Noun chemical_compound Level 1050

methanol

A colorless, volatile, flammable, poisonous alcohol used as a solvent, fuel, and industrial chemical.

Noun chemical_compound Level 1050

monoxide

A chemical compound whose molecules contain one oxygen atom bonded to another element.

Noun chemical_compound Level 1050

nitrate

A salt or ester of nitric acid, containing the nitrate ion NO₃⁻.

Noun chemical_compound Level 1050

oxide

A chemical compound in which oxygen is combined with another element or group of elements.

Noun chemical_compound Level 1050

ozone

A pale-blue gas with a sharp smell, consisting of three oxygen atoms per molecule and formed naturally in the atmosphere or used as a disinfectant.

Noun chemical_compound Level 1050

peroxide

A chemical compound containing an oxygen–oxygen bond, especially one used as an oxidizing agent or disinfectant.

Noun chemical_compound Level 1050

phosphate

A salt or ester of phosphoric acid, containing phosphorus and oxygen, often used in fertilizers, detergents, and biological processes.

Noun chemical_compound Level 1050

propane

A colorless, highly flammable gaseous hydrocarbon (C₃H₈), commonly stored as a liquid under pressure and used as a fuel for heating, cooking, and vehi...

Noun chemical_compound Level 1050

proton

A stable subatomic particle with a positive electric charge, found in the nucleus of an atom; the number of protons determines the atom's atomic numbe...

Noun chemical_compound Level 1050

silica

A hard mineral compound consisting of silicon and oxygen, commonly found in sand, quartz, and many rocks; silicon dioxide.

Noun chemical_compound Level 1050

silicate

A salt or ester containing silicon, oxygen, and usually one or more metals, based on the silicate anion or its structural units; silicates make up man...

Noun chemical_compound Level 1050

sulfate

A salt or ester of sulfuric acid, containing the sulfate ion SO₄²⁻.

Noun chemical_compound Level 1050

sulfide

A chemical compound in which sulfur is combined with a less electronegative element, especially a compound containing the sulfide ion S²⁻.

Noun chemical_compound Level 1050

testosterone

A male sex hormone produced mainly in the testes, and in smaller amounts by the ovaries and adrenal glands, that supports the development of male repr...

Noun chemical_compound Level 1050

urea

A nitrogen-containing chemical compound, CO(NH₂)₂, produced in the liver from the breakdown of proteins and excreted in urine; it is also manufactured...

Noun chemical_compound Level 1050

marijuana

The dried leaves, flowers, and stems of the cannabis plant, used as a psychoactive drug.

Noun chemical_compound Level 1070

herbicide

A chemical used in farming to kill or control unwanted weeds among crops.

Noun chemical_compound Level 1078

pesticide

A chemical used in farming to kill or control pests that damage crops.

Noun chemical_compound Level 1078

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