Why does Silica content in most magmas range from 45 to almost 80 ...

[corkyiscool3328]

Why does Silica content in most magmas range from 45 to almost 80 percent by weight?
 
  A) Silica is very heavy and therefore throws off the percent weight.
  B) Silica is made up of silicon and oxygen, two elements most prevalent in the earth's crust.
  C) Silica is a very heavy gas.
  D) Silica is extremely light.

Question 2

True or False: The composition of the magma determines the minerals that form in an igneous rock.
 
  Indicate whether this statement is true or false.

[Amiracle]

Answer to Question 1

Thank you for answering this question.

Answer to Question 2

Answer: TRUE

[corkyiscool3328]

Gracias!

[xthemafja]

Thanks for the timely response, appreciate it