Chemistry | Definition, Topics, Types, History, & Facts | Britannica
2024年11月5日 · chemistry, the science that deals with the properties, composition, and structure of substances (defined as elements and compounds), the transformations they undergo, and the energy that is released or absorbed during these processes.
Chemical substance - Wikipedia
Chemical substances can exist in several different physical states or phases (e.g. solids, liquids, gases, or plasma) without changing their chemical composition. Substances transition between these phases of matter in response to changes in temperature or pressure.
What is Pure Substance? - Definition, Examples, Difference …
Pure substances are substances that are made up of only one kind of particle and have a fixed or constant structure. Pure substances are further classified as elements and compounds. An element is a substance that consists of only one type or kind of atom.
Substance - 40+ Examples, Definition, Formula, Types, Differences
2024年7月12日 · In chemistry, a substance is any form of matter that has a uniform and unchanging composition. This means that a substance is made of the same material throughout and has specific properties that do not change. Examples of substances include water, salt, …
Chemical compound | Definition, Examples, & Types | Britannica
2024年10月18日 · The substances mentioned above exemplify the two basic types of chemical compounds: molecular and ionic. Methane and water are composed of molecules; that is, they are molecular compounds. Sodium chloride, on the other hand, contains ions; it is an ionic compound.
3.1: Types of Chemical Compounds and their Formulas
2023年7月12日 · Chemical bonds are generally divided into two fundamentally different types: ionic and covalent. In reality, however, the bonds in most substances are neither purely ionic nor purely covalent, but lie on a spectrum between these extremes.
1.4: Classification and Properties of Matter - Chemistry LibreTexts
2023年8月29日 · Any sample of matter that has the same physical and chemical properties throughout the sample is called a substance. There are two types of substances. A substance that cannot be broken down into chemically simpler components is an element. Aluminum, which is used in soda cans, is an element.
3.4: Classifying Matter According to Its Composition
Identify each substance as a compound, an element, a heterogeneous mixture, or a homogeneous mixture (solution). Decide whether a substance is chemically pure.
19 Classification of Matter (Elements, Compounds, Mixtures)
Distinguish chemical substances from mixtures. Matter can be broken down into two categories: pure substances and mixtures. Pure substances are further broken down into elements and compounds. Mixtures are physically combined structures that can be …
Substance Definition, Types & Examples - Lesson - Study.com
2023年11月21日 · What are the types of substances? Types of substances include elements and compounds. Elements can be one atom, or a molecule containing the same atom types. Compounds are also molecules, but...