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Pure substance should have a purity of 100%, but in reality, they are typically not 100% pure. Refining is a method that chemists use to extract pure substances in nature.
However, if you heat it up, the iron and the sulfur would combine chemically, and a new compound would be formed, which we call "iron sulfur" (FeS F e S). This is a new compound and loses the properties of the original compounds. For example, it is not attracted by magnets. Therefore, water is not a mixture; it is a compound and it is pure. Share.
7. Simply, a pure substance is a substance which is composed by molecules or directly by atoms of only one kind. Diamond is a pure substance because it is directly made up of carbon atoms. Salt water is not because it contains sodium chloride and water.
Water is a pure substance, depending upon its variety. For instance, distilled water and seawater have different properties. Seawater contains H 2 O molecules as well as salt molecules and ...
Pure substances are defined as substances that are made of only one type of atom or molecule. The purity of a substance is the measure of the extent to which a given substance is pure. The ...
Wikipedia article. A pure substance cannot be separated by physical means. This means in principle, so if in practice, you cannot separate physically, but you theoretically could, that's still not a pure substance. A compound would then be pure because you cannot separate out its components by physical means.
All generalities are false (as is this one). Though impurities usually lower the melting point (m.p.) by disrupting crystallization on the atomic order, consider the phase diagram of the binary alloy (amalgam) Hg x Ag 1- x: Pure Hg melts ~-39°C, and adding even a little bit of impurity raises the melting point considerably!
The density of a pure substance remains constant regardless of changes in mass or volume. Density is a physical property that is inherent to a substance and is calculated as mass divided by volume.
The presence of impurities in a substance results in a lower melting point due to a process called melting point depression. Melting point depression is the reason why adding salt to frozen streets helps to melt the ice. Melting point depression occurs due to the nature of a material's solid state.
This binary phase diagram has pure A on the left, pure B on the right. A and B form, somewhere, a eutectic. It is the point here at concentration e and temperature y. Because the existence of a eutectic point is guaranteed for any A/B binary system, and because the eutectic corresponds to a lower temperature, your liquidus curve decreases with ...