0.500 L (1.00 moles KCl/L) = 0.500 moles KCl0.500 moles KCl (74.5 grams KCl/mole) = 37.3 g KCl29 . D
This reaction is a synthesis reaction as well as an oxidation-reduction reaction. The hydrogen
is being oxidized and the chlorine is being reduced. While HCl, an acid, is being produced, this
is not a neutralization reaction because the acid and a base would have to be present as
reactants.
30 . B
All of the other reactions are oxidation-reduction reactions. Reaction B is a double-
displacement reaction that is also a neutralization reaction. There is no transfer of electrons—
only protons.
31 . C
The heat of formation for an element in the natural state is 0.
32 . B
Hess’s law is used to combine the two reactions to the given reaction for the formation of SO 3
(g). The first reaction is used as written while the second reaction is divided by two, since only
1 SO 3 is in the reaction provided.
So the heat of reaction is the sum of (−297) + (−99) = −396 kJ.33 . E
MgO is a white, crystalline solid. C 3 H 8 and CO are both colorless gases. CuCl 2 is a brownish
yellow solid. Cr 2 O 3 is a green solid. The transition metals tend to form colored products.
34 . E
MgO is an ionic compound. Ionic compounds have higher melting points than covalent
compounds. The other four compounds are all covalent compounds, which have lower boiling