Nitrogen has an average atomic mass of 14. 674. It has two isotopes, n-14 and n-15, with atomic masses of 14. 0031 amu and 15. 001 amu, respectively. What is the abundance of n-15?.

Aroller coaster car is traveling down a track at 22 m/s. the car has a mass of 2000 kg. what is the kinetic energy of the car? a) 22,000 j b) 968,000 j c) 484,000 j d) 44,000 j

If 34.2 grams of lithium react with excess water, how many liters of hydrogen gas can be produced at 299 kelvin and 1.21 atmospheres? 2 li (s) + 2 h2o (l) yields 2 lioh (aq) + h2 (g)

According to each substances heat of fusion, which of the items below requires more heat to be added per gram of substance to go from solid to liquid? silver sulfur water lead