Barium sulfate, #BaSO_4#, is so insoluble that it can be swallowed without significant danger, even though #Ba_2^+# is toxic. At 25 °C, 1.00 L of water dissolves only 0.00245 g of #BaSO_4#. How do you calculate Ksp for #BaSO_4#?

1 Answer

Answer:

#1.1 xx 10^-10#

Explanation:

#BaSO_4(s)⇌Ba^(2+)(aq)+SO_4^(2-)(aq)#

Moles of dissolved #"BaSO"_4 = "0.00245 g" / "233.43 g/mol" = "0.0000105 mol"#;

#[Ba^(2+)]= [SO_4 ^(2-)]# (As both are equal according to moles)

= #"0.0000105 mol"/"1.00 L" = 0.0000105 M#;

#K_(sp) = [Ba^(2+)][SO_4^(2-)]=(0.0000105)^2 = 1.1 xx 10^-10#