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An element is a type of matter composed of atoms that all have exactly the same positive charge on their nuclei. In other words, all atoms of an element have the same atomic number.
A chemical compound is a pure chemical substance consisting of two or more different chemical elements that can be separated into simpler substances by chemical reactions
A pure substance is any single type of material.
A substance can be anything. It doesn't have to consist of a single element or type of molecule. Pure hydrogen is a pure substance. So is pure honey, even though it consists of many different types of molecules. What makes both of these materials pure substances is that they are free from contamination. If you add some oxygen to the hydrogen, the resulting gas is neither pure hydrogen nor pure oxygen. If you add corn syrup to the honey, you no longer have pure honey. Pure alcohol could be ethanol, methanol or a mixture of different alcohols, but as soon as you add water (which is not an alcohol), you no longer have a pure substance.
A mixture consist of two or more different substances that are mixed but not chemically combined together.
Mixtures can be either homogeneous or heterogeneous. A homogeneous mixture is a type of mixture in which the composition is uniform . A heterogeneous mixture is a type of mixture in which the components can easily be identified, as there are two or more phases present
A chemical compound is a pure chemical substance consisting of two or more different chemical elements that can be separated into simpler substances by chemical reactions
A pure substance is any single type of material.
A substance can be anything. It doesn't have to consist of a single element or type of molecule. Pure hydrogen is a pure substance. So is pure honey, even though it consists of many different types of molecules. What makes both of these materials pure substances is that they are free from contamination. If you add some oxygen to the hydrogen, the resulting gas is neither pure hydrogen nor pure oxygen. If you add corn syrup to the honey, you no longer have pure honey. Pure alcohol could be ethanol, methanol or a mixture of different alcohols, but as soon as you add water (which is not an alcohol), you no longer have a pure substance.
A mixture consist of two or more different substances that are mixed but not chemically combined together.
Mixtures can be either homogeneous or heterogeneous. A homogeneous mixture is a type of mixture in which the composition is uniform . A heterogeneous mixture is a type of mixture in which the components can easily be identified, as there are two or more phases present