chemistry
posted by Fai .
Concentrated hydrochloric acid is a 38% solution of hcl in water and has a density of 1.18g/ml. How many milliliters of concentrated hydrochloric acid are needed to prepare 500ml of a 1:200 hcl solution?
My calculation
500ml x 1:200 =2.5 1:200 means 1gm/200ml
2.5 x 36.5 = 91.25
91.25/0.38=240.13
240.13/1.18 = 204ml This is my answer. I am not sure. Pls helps me .

dude that's very messed up
solution:
first calculate the molarity from % concentration and take volume to be 1L
==>
d=m/v
m=d*v
m=1000ml*1.18g/ml=1180g.
molarity=(1180/36.5)/1L=32.32M
using c1v1=c2v2
v1=c2v2/c1
v1=((1/200)*500)/32.32=0.077ml