Question

describe the steps to take in diluting a solution of 0.500M HCL to make 250 ml. of 0.100 M HCL.

Answer 1

we know that

moles = molarity x volume (ml) / 1000

so

moles of HCl required = 0.1 x 250 / 1000

moles of HCl required = 0.025

now

this moles should come from 0.5M HCl

now

volume required = moles x 1000 / molarity

volume required = 0.025 x 1000 / 0.5

volume required = 50 ml

so

50 ml of 0.5 M HCl is required

now

water needed = final volume - initial volume

water needed = 250 - 50 = 200

so

the steps are

1) take 50 ml of 0.5 M HCl

2) add 200 ml of water to make the solution 250 ml