For the elements, color does not vary much from one element to the next. The vast majority of elements are colorless, silver, or gray. Some elements do have distinctive colors: sulfur and chlorine are yellow, copper is of course copper-colored, and elemental bromine is red.
However, density can be a very useful parameter for identifying an element. Of the materials that exist as solids at room temperature, iodine has a very low density compared to zinc, chromium, and tin. Gold has a very high density, as does platinum. Pure water, for example, has a density of 0. Notice that corn oil has a lower mass to volume ratio than water. Hardness helps determine how an element especially a metal might be used. Many elements are fairly soft silver and gold, for example while others such as titanium, tungsten, and chromium are much harder.
Carbon is an interesting example of hardness. In graphite, the "lead" found in pencils the carbon is very soft, while the carbon in a diamond is roughly seven times as hard. Melting and boiling points are somewhat unique identifiers, especially of compounds. In addition to giving some idea as to the identity of the compound, important information can be obtained about the purity of the material.
Chemical properties of matter describe its potential to undergo some chemical change or reaction by virtue of its composition. The elements, electrons, and bonds that are present give the matter potential for chemical change. It is quite difficult to define a chemical property without using the word "change".
Eventually, after studying chemistry for some time, you should be able to look at the formula of a compound and state some chemical property. Some other fascinating, less well known materials include nanofibres , biological materials and composites.
When we refer to the properties of a material, we are talking about features we can sense, measure or test. For example, if we have a sample of metal in front of us, we can identify that this material is grey, hard and shiny. Testing shows that this material is able to conduct heat and electricity and that it will react with an acid.
It is important to decide if you are investigating the properties of a material or of an object. For example, are you identifying the properties of a spoon an object , or are you looking at properties of the material it is made of, for example, stainless steel?
Properties like shape and mass may be different for different objects, even when they are made of the same material.
Density is a useful property for making comparisons between different materials. Other properties of materials can include their viscosity and conductivity. A commonly talked about property is the state or phase of matter.
There are currently five different states of matter that have been identified: solids, liquids, gases, plasma and Bose-Einstein condensate. The last two of these are much less well known. It is important to note that the state of matter refers to the positioning and movement of the particles that make up a material and not the material itself.
You can learn more about states of matter in the article States of matter. Sometimes it can be useful to distinguish between different types of properties. Physical properties refer to properties that can be observed or measured without changing the composition of the material. All samples of a pure substance have the same chemical and physical properties. For example, pure copper is always a reddish-brown solid a physical property and always dissolves in dilute nitric acid to produce a blue solution and a brown gas a chemical property.
Physical properties can be extensive or intensive. Extensive properties vary with the amount of the substance and include mass, weight, and volume. Intensive properties , in contrast, do not depend on the amount of the substance; they include color, melting point, boiling point, electrical conductivity, and physical state at a given temperature. For example, elemental sulfur is a yellow crystalline solid that does not conduct electricity and has a melting point of As mass increases in a given volume, density also increases.
For example, lead, with its greater mass, has a far greater density than the same volume of air, just as a brick has a greater density than the same volume of Styrofoam. At a given temperature and pressure, the density of a pure substance is a constant:. Pure water, for example, has a density of 0. Notice that corn oil has a lower mass to volume ratio than water.
Physical changes are changes in which no chemical bonds are broken or formed. This means that the same types of compounds or elements that were there at the beginning of the change are there at the end of the change.
Because the ending materials are the same as the beginning materials, the properties such as color, boiling point, etc will also be the same. Physical changes involve moving molecules around, but not changing them. Some types of physical changes include:.
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