Answers

2014-09-15T21:39:26+08:00
V1=(c2v2)/c1
where c1=concentration of first solution
  v1=volume of 1st solution
 c2=concentration of 2nd solution
 v2=volume of 2nd solution
v1=(3.5M(75ml))/12M
v1=262.5/12
v1=21.875ml or 21.9 ml
 therefore answer is letter a
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