Which describes an atom that has fewer neutrons than protons and more electrons than protons? negative compound
positive compound
positive ion
negative ion

Note the ph and poh values labeled with letters on the ph scale below. based on log rules and the way ph is calculated, what is the difference in [oh– ] concentration between point a and point b. a) 10^1 b) 10^5 c) 10^6 d) 10^7

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.

State one important difference between a physical change and a chemical change?