How does the reaction outlined here demonstrate the conservation of mass? The energy stored in the bonds was conserved both before and after the reaction.

The number of atoms before they rearranged is equal to the number of atoms after they rearranged.

The number of molecules both before and after the reaction is constant.

Energy was utilized to transform the arrangement of some atoms to a different arrangement.

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.