A 28.02 g sample of N2 reacts with 2.016 g of H2 to form ammonia if ammonia is the only product what mass of ammonia is formed?

Your friend offers to show you an intrusive igneous rock. which of the following would you expect to see?

Nebulae are enormous clouds in outer space. they are made mostly of hydrogen gas, helium gas, and dust. some nebulae glow brightly, while others do not. the stars that people see are huge, bright balls of glowing gas. they are made mostly of hydrogen and helium. which statement correctly describes other ways in which nebulae and stars are different? a. stars can form inside a nebula but a nebula can never be produced by any star. b. a star always has a higher density than a nebula. c. stars can never form inside a nebula but a nebula can be produced by any star. d. a nebula always has a higher density than a star.

As changes in energy levels of electrons increase, the frequencies of atomic line spectra they emit