Water vapor condenses into a glass of water. The water is then placed in a freezer and changes into ice. What remains
consistent as the water changes states?

Determine the wavelength of the light absorbed when an electron in a hydrogen atom makes a transition from an orbital in the n=3 level to an orbital in the n=7 level.

How are isotopes of the same chemical element alike? how are they different?

Which of the following is an example of physical change not a chemical change? a) a log gives off heat and light as it burns. b) a tree stores energy from the sun in its fruit. c) a penny lost in the grass slowly changes color. d) a water pipe freezes and cracks on a cold night.