Apure substance that cannot be broken down into any other substance by a physical or chemical means is a (n)

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

Agas occupies 475 cm^3 at 313k. find its volume at 367k. you must show all of your work to receive credit. be sure to identify which of the gas laws you will be using

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.