Define alloys. List the properties of alloys that make them useful over pure metals. Explain this fact with suitable examples.

(N/A) An alloy is a homogeneous mixture of two or more metals,or a metal and a non-metal,which cannot be separated into its components by physical methods.
Properties that make alloys more useful than pure metals:
$(i)$ Alloys are often harder and stronger than their constituent pure metals.
$(ii)$ They are more resistant to corrosion.
$(iii)$ Their electrical conductivity is generally lower than that of pure metals.
$(iv)$ Their melting point is lower than that of pure metals.
Examples:
$(a)$ Brass (an alloy of $Cu$ and $Zn$) and Bronze (an alloy of $Cu$ and $Sn$) are not good conductors of electricity,whereas pure copper is an excellent conductor used in electrical circuits.
$(b)$ Solder (an alloy of $Pb$ and $Sn$) has a very low melting point,making it ideal for welding electrical wires together.