Question 803228
In other words, how much solvent to add?
The amount of Mag Sulfate does not change
I will say I have {{{ x }}} ml to start with
Let {{{ y }}} = ml of solvent to be added
{{{ .5x / ( x + y ) = .2 }}}
{{{ .5x = .2*( x + y ) }}}
{{{ .5x = .2x + .2y }}}
{{{ .2y = .5x - .2x }}}
{{{ .2y = .3x }}}
{{{ y = (3/2)*x }}}
Add 1 and 1/2 times as much solvent as the 
ml of total solution you started with