Which statement correctly describes an atom of the element helium? a. an atom of helium has a full outer energy level and is therefore unusually reactive. b. an atom of helium most similarly behaves like an atom of hydrogen since it is in the same period. c. an atom of helium has its valence electrons in its first energy level. d. an atom of helium has eight electrons in its outer energy

Select the correct answer. when carbon dioxide dissolves in water, it sometimes reacts with water to form carbonic acid as in this balanced equation: co2 + h2o → h2co3. if 495 milliliters of carbon dioxide at 25°c and 101.3 kilopascals reacts with excess water, what is the theoretical yield of carbonic acid? use the periodic table and the ideal gas resource a. 0.889 g b. 1.10g c. 1.27g d. 2.02g what's the answer! quick!