How do you calculate the number of moles of solute in 98.97 mL of 0.1585 M #K_2Cr_2O_7 (aq)#?

1 Answer
Dec 24, 2017

Simply take the product...#"volume"xx"concentration"# to give an answer in #"moles"#.

Explanation:

By definition, #"Concentration"="Moles of solute"/"Volume of solution"#.

And thus #n_"moles of solute"="concentration"xx"volume"#

#=0.1585*mol*L^-1xx98.97*mLxx10^-3*L*mL^-1=??*mol#

Note the dimensional consistency of the product. We wanted an answer in moles, and the product gave us one....i.e.

#0.1585*mol*cancel(L^-1)xx98.97*cancel(mL)xx10^-3*cancel(L*mL^-1).#

#=??mol#