Antimony, when alloyed with lead, improves its ___ .
Hardness and strength
Conductivity
Resistivity
None of the above
Alloys increase the strength of the element. Lead is a soft metal, thus needs to be alloyed with antimony.
When Iron is alloyed with a non-metal, a hard substance called as steel is formed. The substance which is used to make it hard is ___ .