How is the purity of substances important?​

Pure substances have the ability to form predictable outcomes from their chemical reactions. Chemists tend to use pure substances when conduction chemial research as impure substances can mess up their experiments.

shield volcanos are angry and get mad over the smallest things so much that there heads erupt   pahoehoe and a'a lava. a composite volcano is the poller opposite of a shield volcano. its   peaceful thing and knows how to control its emotions.      

i think its 100

i hope this !