Metals are distinguished by their high electrical and thermal conductivity, malleability, ductility, and luster. They are typically solid at room temperature (except for mercury), have a high melting point, and are capable of forming positive ions in chemical reactions. Metals also tend to have a crystalline structure and are good at reflecting light, giving them their characteristic shiny appearance. **

Metals have several properties that distinguish them from other materials. They are typically shiny, malleable, and ductile, meaning they can be easily shaped and formed without breaking. Metals are also good conductors of heat and electricity, and they have high melting and boiling points. Additionally, metals are usually dense and have a metallic luster. These properties make metals useful in a wide range of applications, from construction and manufacturing to electronics and transportation. **

Alkali metals are highly reactive and easily lose their outermost electron to form a +1 cation. They have low melting and boiling points, making them soft and easily cut with a knife. Alkali metals are good conductors of heat and electricity. They are typically stored under oil to prevent them from reacting with moisture and oxygen in the air. **

Ferrous metals are metals that contain iron, such as steel and cast iron. These metals are known for their strength and durability, making them commonly used in construction, manufacturing, and automotive industries. Ferrous metals are also magnetic and have good conductivity, making them versatile for various applications. **

Precious metals are rare, naturally occurring metallic elements that have high economic value. Examples of precious metals include gold, silver, and platinum. These metals are often used in jewelry, investment, and industrial applications. On the other hand, base metals are more common metallic elements that are not as valuable as precious metals. Examples of base metals include copper, zinc, and nickel. These metals are widely used in construction, manufacturing, and electrical applications. **

Base metals can precipitate noble metals through a process called cementation. This occurs because base metals have a higher reactivity compared to noble metals. When a base metal is in contact with a solution containing a noble metal ion, the base metal will oxidize and release electrons, causing the noble metal ion to be reduced and form a solid precipitate on the surface of the base metal. This allows for the separation and recovery of noble metals from a solution containing a mixture of different metals. **

Alkali metals are called alkali metals because they form alkaline solutions when they react with water. When alkali metals such as lithium, sodium, and potassium come into contact with water, they produce hydroxide ions, which make the solution alkaline. This property of forming alkaline solutions is the reason why they are called alkali metals. **

Metals increase mechanical properties of strength and hardness through their crystalline structure. The arrangement of atoms in a metal's crystal lattice allows for the movement of dislocations, which are defects in the lattice that allow for plastic deformation. The presence of dislocations makes it more difficult for layers of atoms to slide past each other, increasing the metal's strength. Additionally, the presence of alloying elements or impurities can also strengthen the metal by disrupting the crystal lattice and creating obstacles that hinder dislocation movement. Hardness is also increased by the presence of alloying elements, which can form compounds or solid solutions that resist deformation and make the metal more resistant to scratching or indentation. **