Farzana Jalil AS1D
We use metals in many different ways. Our lives wouldn’t be the same without them, especially living in a country as industrial as Britain. In this presentation I will talk about some examples of metals such as copper, aluminium, steel and mercury and I will discuss with you their properties and how it relates to their use.
Properties of Metals
- Both heat and electricity flow easily through all metals; therefore they are good conductors of heat and electricity and this is one of the common ways of distinguishing between metals and non-metals. If we know that a substance conducts electricity, then we are almost certain that it is a metal. The only non-metal that conducts electricity well is a type of carbon called graphite.
- Metals have a high tensile strength. This means that they are very strong and tough. This is due to the strong bond that exist between the metal particles and that is why they make good building material.
- Metals are shiny when polished or freshly cut. They give a strong reflection of light from their smooth surface, which makes them look shiny.
- Metals are malleable, which means they can be easily shaped. This is because the bonds inside them are strong, which makes them able to withstand stresses and movement. They are tough and don not shatter easily but we can force a metal to bend into a different shape.
- Metals are sonorous; they make a sound when you hit them.
- Metals are ductile, which means they can be drawn into wires. The bonds in the metal don’t break easily so they aren’t brittle like non-metals. They bend and stretch.
- Metals have high melting and boiling points. A lot of heat energy is needed to melt metals. This is because their atoms join up with strong bonds. Mercury is an example of a metal that is liquid at room temperature but we can melt all metals if we heat them enough.
- Metals have high densities as they have a lot of atoms packed into a small volume.
- Some metals are magnetic. In the periodic table they are only iron, nickel and cobalt. An alloy made up of these three metals will also be magnetic. Steel is made mostly from iron and is also magnetic.
- Metals make alloys when mixed with other metals. An alloy is basically a combination of different metals. The properties of the metals get jumbled up in the new alloy so light, weak metals can be mixed with heavy, strong metals. The result of this is hopefully an alloy, which is light and strong.
