Question #198a3

1 Answer
May 11, 2017

We exploit the stoichiometric reaction............

Explanation:

#Ba(NO_3)_2(aq) + Na_2CO_3(aq) rarr BaCO_3(s)darr+2NaNO_3(aq)#

Most carbonates are insoluble; the alkaline earth carbonates are especially insoluble. #BaCO_3# has #K_(sp)=2.58xx10^-9# (these data should have been supplied with the question).

Addition of stoichiometric sodium carbonate should suffice.

#"Moles of barium nitrate"=120xx10^-3*Lxx0.0500*mol*L^-1=6xx10^-3*mol.#

And thus we need.....................................................................

#6xx10^-3*molxx105.99*g*mol^-1=635*mg# with respect to #"sodium carbonate"#.