Acertain radioactive element has a half-life of one hour. if you start with 40.0 grams of the element at noon, how much of the radioactive element will be left at 2 p. m.? (3 points)
0.0 grams
10.0 grams
20.0 grams
5.0 grams

What is the overall order of reaction for rate = k[no2]2 ? second order 3/2 order third order zero order none of the listed answers are correct

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!

What are the similarities of physical and chemical change ?