What is the size range of particles in a colloid? a) between 1 nm and 1000 nm b) between 1 nm and 10 nm c) between 100 nm and 1000 nm d) between 1000 nm and 2000 nm

An experimental procedure requires a 10 ml of acid to be dissolved

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