Which best represents a balanced equation? A. HgO → Hg + O2
B. 2Fe + O2 → Fe2O3
C. 2H2 + 02->2H2O

Which statement best describes the relationship between period and frequency of light waves? a) in wave b the period increases and the frequency decreases from wave a. b) in wave a the period increases and the frequency decreases from wave b. c) in wave b the period is shorter and the frequency is greater than in wave a. d) in wave a the period is shorter and the frequency is greater than in wave b.

Which set of characteristics best describes igneous rock? a) largest type of rock, made of organic matter, hardest type of rock b) least abundant type of rock, made of other rocks, made mostly of minerals c) found on all continents, contains wavy bands of stripes, contains fossils d) most abundant type in earth's crust, made of magma/lava, contains no fossils

Which of the following warnings would an agricultural chemist tell a farmer who wants to recycle his or her own ammonia? recycling ammonia is a difficult process that sometimes takes weeks. recycling ammonia requires a degree in biochemistry or a related field. recycling ammonia can be harmful because it is highly flammable and toxic. recycling ammonia costs too much money considering the price of the necessary chemicals.