What is the concentration of H2O2 in a solution that is 30.0% by mass hydrogen peroxide and has a density of
1.11 g cm-3?
(A) 9.79 M
(B) 12.6 M
(C) 18.5 M
(D) 32.6 M
6. A 5.00 g mixture of potassium sulfide and potassium
chloride contains 2.80 g potassium. What percentage by
mass of the mixture is potassium sulfide?
(A) 13.8%
(B) 19.2%
(C) 44.0%
(D) 96.1%
7. Which salt dissolves in water to give a pink solution?
(A) Co(CH:COO)2
(B) CuSOA
(C) Fe(N03)3
(D) ZnCh