Alloys and Metals

if boron 84pm and carbon 69pm are combined what type of alloy is created

if flourine 64 pm and lithium 121pm combine what type of combination will occur

type of attraction that holds metal atoms togather

in an interstitial alloy atoms------ while they---------- in a substitutional alloy

Many metals are alloyed in order to increase their strength.  Gold can be alloyed with many metals.  For example, gold (radius 144 pm) and silver (radius 144 pm) can be alloyed to form white gold.  Which of the following metals would be best to make a substitutional alloy with gold?