Compounds mixtures and elements worksheet.The compounds are pure substances. They are made from the same types of molecules.
Each molecule of a compound is composed of at least two types of chemically linked atoms. Mixtures are composed of two or more substances – elements or compounds – physically mixed but not chemically; they do not contain atomic bonds.
Comparative table compound / mixture
|Definition||A compound contains atoms of different elements chemically combined in a fixed ratio.||A mixture is a combination of two or more substances without chemical combination or reaction.|
|Composition||The compounds contain different elements in a fixed ratio defined in a manner defined by chemical bonds. They contain only one type of molecule. The elements that make up the compound are chemically combined.||The mixtures contain different elements and compounds, but the ratio is not fixed or combined by chemical bonds. The ingredients are physically mixed but chemically separated. Often, they are visibly distinct.|
|Representation||A compound is represented using its chemical formula which represents the symbols of its constituent elements and the number of atoms of each element in a molecule of the compound.||Mixtures can not be represented by a formula.|
|Examples||Water (H2O), sodium chloride (NaCl), sodium bicarbonate (NaHCO3), etc.||Salt in the water, pasta and sauce, sand and pebbles.|
|Ability to fail||A compound can be separated into simpler substances by chemical methods / reactions.||A mixture can be separated into simpler substances by physical methods.|
|Types||A huge, virtually unlimited number of chemical compounds can be created. The compounds are classified into molecular compounds, ionic compounds, intermetallic compounds and complexes.||Solids, liquids and gases can be combined to create a mixture. The mixtures may be homogeneous or non-homogeneous.|
|Chemical and physical properties||The compounds have specific chemical and physical properties that are distinct from their constituent elements because the constituent elements lose their properties when they combine to form the compound.||The mixtures do not have specific and consistent chemical and physical properties. They reflect the properties of their components, which retain their original properties. for example. Chocolate milk retains the properties of chocolate and milk|
|Mass ratio||The compounds have specific mass ratios. for example. pyrite contains 46.6% iron and 53.4% sulfur by weight. This is true of all pyrite, no matter the size of the sample.||The blends have a variable mass ratio depending on the amounts of ingredients combined in the blend.|
Constituents of compounds mixtures and elements worksheet
The compounds are composed of elements, which are pure substances with only one type of atoms.
The atoms of the elements form bonds to combine and form a molecule of the compound. The compound contains a uniform distribution of these molecules.
A compound has different physical and chemical characteristics than its components. It is not possible to see the elements when you see the compound.
For example. the water is composed of hydrogen and oxygen, but you can not see either element separately when you look at the water.
Salt is composed of sodium and chloride, but its physical and chemical properties are completely different from those of sodium or chloride.
Types of materials: elements, compounds, homogeneous and heterogeneous mixtures.
Both elements and compounds are called pure substances because they contain only one type of molecule.
A mixture contains two types of pure substances or more. The molecules of these substances do not form chemical bonds in a mixture.
The components of a mixture retain their chemical independence but physically blend into each other. It is often possible to see these components and differentiate them visually.
The constituent elements of a compound can only be separated by means of a chemical reaction that breaks the atomic bonds that bind its molecules.
The ingredients of a mixture can be separated by physical means such as sedimentation or decantation.