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עמוד:23
Properties of metals and non-metals We can distinguish metals by their appearance – most of them are silvery and have a metallic sheen . Metals also have some other properties in common : most can be worked , meaning , they can be hammered ( to obtain a thinner thickness of the metal ) , and bent – without them breaking or crumbling . Also they are good conductors of electricity and heat . Non-metals differ from metals in their appearance as well as in other properties : they are not silvery and most are not shiny , they tend to break and crumble , and they are bad conductors of electricity and heat . It is also important to mention another group of elements – the metalloids . These are elements that possess some of the properties of the metals and some of the properties of the non-metals . The most famous element in this group is silicon , one of the most important materials in the electronics industry . For the time being we will focus on the division into metals and non-metals only . In the periodic table , the metals are located in the center and on the left , and the non-metals are on the right . The metalloids are located in the periodic table at the meeting point between the metals and the non-metals . Did you know ... Why do metals conduct electricity ? All metals conduct electricity . Why ? The ability of metals to conduct electricity can be explained through the structure of the metal particles . In most metals , the atoms form a structured formation called a metal lattice ( crystal ) . In an atom of metal , some of the electrons are only weakly attracted to the nucleus , and they can therefore break away from the atom relatively easily and move freely among the other atoms . These electrons are called free electrons . The good electric conductivity of the metals is the result of the movement of these free electrons within the metal . Metals Non-metals Silicon is a metalloid Aluminum is a metal Sulfur is a non-metal
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