Phase A phase is any part of a sample that has a uniform composition and properties. If it is pure, the substance is either an element or a compound. If a substance can be separated into its elements, it is a compound. If a substance is not chemically pure, it is either a heterogeneous mixture or a homogeneous mixture. If its composition is uniform throughout, it is a homogeneous mixture. Solution A Tea is a solution of compounds in water, so it is not chemically pure.
It is usually separated from tea leaves by filtration. B Because the composition of the solution is uniform throughout, it is a homogeneous mixture. A Orange juice contains particles of solid pulp as well as liquid; it is not chemically pure. B Because its composition is not uniform throughout, orange juice is a heterogeneous mixture. A A compact disc is a solid material that contains more than one element, with regions of different compositions visible along its edge. Hence, a compact disc is not chemically pure.
B The regions of different composition indicate that a compact disc is a heterogeneous mixture. A Aluminum oxide is a single, chemically pure compound. A Selenium is one of the known elements. Saltwater is a homogeneous mixture, or a solution.
Soil is composed of small pieces of a variety of materials, so it is a heterogeneous mixture. Water is a substance. More specifically, because water is composed of hydrogen and oxygen, it is a compound. Oxygen, a substance, is an element. Summary Matter can be classified into two broad categories: pure substances and mixtures. Vocabulary Element: a substance that is made up of only one type of atom. Heterogeneous Mixture. Heterogeneous mixtures are those where there is a lack of uniform composition.
A mixture of soil and sand, oil and water, sulphur and iron filings and many more are the examples of heterogeneous mixtures. In this, the boundaries of the constituent particles can be identified easily because it has two or more distinct phases. It is rarely possible to separate the particles from each other. Sometimes some mixtures appear as heterogeneous at a normal scale become more homogeneous on a large scale. For instance- Sand is a heterogeneous mixture if you examine it in the palm of your hand and seems homogeneous if you have a view of an entire beach.
Here, some properties of the heterogeneous mixture are explained below for better understanding. The Properties of a Heterogeneous Mixture are as Follows:. In a heterogeneous mixture, the constituent particles are present uniformly. Most of the mixtures are heterogeneous except alloys and solutions. You can identify the components easily in the heterogeneous mixture.
The particles show a Tyndall effect. The size of the particles is between one nanometer and one micrometer. A compound is the substances that are formed by combining two are more chemical elements. A mixture is a substance created from two or more matter that can be separate with the help of physical methods. Compound substances are always homogeneous in nature.
Nature of Mixture substances can either be homogeneous or heterogeneous. A mixture of oil and water, sand and soil, sulphur and iron filings, smoke and fog smog etc are some examples. Compounds are of three types i. Moreover, compounds can also be classified as organic or inorganic compounds based on the presence of the carbon atom. There are two main types of mixture i. Substance category. Mainly pure water is part of the compound.
Mixtures fall under impure water. Separation of constitution. The only methods that can be separate constituents of compounds are chemical and electrochemical like extraction. The constituents of a mixture can easily be separated by physical like filtration method. The ratio of the elements in compounds is always fixed. They contain only one type of molecule.
Also, the elements chemically combined. Whereas, a mixture can have a variable composition of substance in forming but the ratio is not fixed nor they are combined via chemical bonds. A compound is represented using its chemical formula. The word 'pure' is used in chemistry in a different way from its everyday meaning.
For example, shops sell cartons labelled as 'pure' orange juice. The label means that the contents are just orange juice, with no other substances added. However, the juice is not pure in the chemical sense because it contains different substances mixed together.
In chemistry:. Hydrogen and oxygen are both gases. Together, as a mixture, hydrogen and oxygen can react and form water. Water is a compound of hydrogen and oxygen. There are important differences between the properties of a mixture and a compound. In this table, the column 'Mixture' refers to the gasses hydrogen and oxygen, and the column named 'Compound' refers to water.
Pure substances have a sharp melting point but mixtures melt over a range of temperatures.
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