What is the molal concentration of lead nitrate in 0.726 M #Pb(NO_3)_2#?

density = 1.202 g/ml

1 Answer
Dec 9, 2016

#0.755m#

Explanation:

I originally misread the question and thought the user was asking for molar concentration.

#0.0726*mol*331.22g*mol^-1#
#=24.05g*PbNO_3# in #100ml# of #0.725M# solution.

Subtract, density tells us its #1.202g*ml^-1# so,

#120.2g-24.05g=96.15g#

#96.1534g*(1kg)/(1000g)=0.09615kg#

And now we have:

#m=#molality# = (mol)/(kg)#

#m=##(0.0726*mol)/(0.09615*kg)#

#= ##0.755m#