40g of NaOH is added to water to create 1 L of solution. The resulting solution has a SG of 1.07. a) Calculate the mass (in lb) of 1 L of solution? b) Calculate the molecular mass of NaOH? c) Calculate the molarity of NaOH in the solution.?

1 Answer
Oct 16, 2017

We know that the density of the solution, #rho_"solution"=1.07*g*mL^-1#

Explanation:

#a.# And so if we gots a #1*L# volume....then we have a mass of.....

#1000*mLxx1.07*g*mL^-1=1070*g#..

But #1*lb-=454*g#...

And so #1070*g-=1070*gxx1/(454*g*lb^-1)=2.36*1/(lb^-1)# #=2.36*1/(1/(lb))=2.36*lb#

#b.# And the molar mass of #NaOH# is simply....

#(22.99+15.999+1.00794)*g*mol^-1=40.0*g*mol^-1#.

#c.# And the molarity is simply the quotient....

#"Molarity"="Moles of solute"/"Volume of solution"#

#=((40*g)/(40.0*g*mol^-1))/(1.00*L)=1.00*mol*L^-1#.....

I don't know why the septic tanks don't go back to using pounds, shillings, and pence if they are bent upon using #"lbs"#, and #"inches"#, and #"tons"#. And while they are at it, they could recognize Queen Elizabeth II as their lawful sovereign.