Metals And Alloys Flashcards
What do metals consist of ?
Giant structure of atoms arranged in regular layers
The electrons in the putter energy level of each atom are delocalised so there is a sea of delocalised electrons
What is the key fact !
Strong electrostatic attraction between the sea of delocalised negative electrons and the positive metal ions
What is the force of attraction in metal bonds ?
Electrostatic attraction, between metals and this is a metallic bond which is strong
Why do metals have a high melting and boiling point ?
Metals have got a high melting and boiling point because a great deal of energy is required to break the strong metallic bonds
Why do metals conduct electricity ?
Metals are excellent conductors of heat and electricity because there is a sea of free to move delocalised electrons, because the electrons are charged they can carry an electrical current this also allows them to carry thermal energy
Why can metals be bent and shaped ?
In metals the atoms are arranged in repeating layers that are able to slide over each other
Why might we alloy a metal ?
To make it harder as some metals such as gold are too soft to be useful
What is an alloy ?
A mixture of metals
Why are alloys harder than pure metals ?
The different sizes of atoms distort the layers, making it more difficult for them to slide over each other therefore alloys are harder than pure metals
