Magnesium Sulfate Can Be Obtained at a Drugstore as Epsom $K _ { \mathrm { a } _ { 2 } }$

Multiple Choice

Magnesium sulfate can be obtained at a drugstore as Epsom salts. The monohydrate is found as the mineral kieserite (MgSO₄ . H₂O, 138 g/mol) . What would be the pH of a 500 mL aqueous
Solution containing 1.62 g of dissolved kieserite? The $K _ { \mathrm { a } _ { 2 } }$
Value for sulfuric acid is 1.2 *10^-2.

A) 7.00
B) 6.85
C) 7.15
D) 3.55
E) 12.22