(A) I only
(B) II only
(C) III only
(D) I and II
(E) II and III67 . When 200 g of MgCl 2 is added to 1 kg of water, what is the molality of the solution?
(A) 200/(24 + 71)
(B) 0.200/(24 + 71)
(C) 0.2(24 + 71)
(D) 0.200
(E) 20068 . How many moles of water are formed by a mixture of 100 grams of H 2 and 100 grams of
O 2 ? (Assume the reaction goes to completion.)
(A) 100/32 + 100/64
(B) 100 + 2(100/32)
(C) 2(100/32)
(D) 100(100/32)
(E) 200(100/32)69 . An oxide of arsenic contains 65.2% arsenic by weight. What is its simplest formula?
(A) AsO
(B) As2O 3
(C) AsO 2
(D) As 2 O 5
(E) As 2 O