Some common mouth problems include. 1  Cold sores - painful sores on the lips and around the mouth, caused by a virus. 2  Canker sores - painful sores in the mouth, caused by bacteria or viruses. 3  Thrush - a yeast infection that causes white patches in your mouth.
-Explain why energy input is necessary to extract a metal from its ore In order to break the chemical bonds in the compounds, energy such as heat or electricity is required to break these bonds and extract the metal. -Identify why there are more metals available for people to use then there were 200 years ago.etal + Oxygen Metal Oxide Metals with a low reactivity such as gold and silver are used in jewellery because of their shiny lustre and the fact that they do not tarnish easily. with a particular emphasis on current developments in the use of metals. This is because the metal tends to want to keep its electrons more.
When a metal ore is an ionic compound of that metal and a non-metal, the ore must usually be smelted â heated with a reducing agent â to extract the pure metal. Many common metals, such as iron, are smelted using carbon as a reducing agent.