When water is moved through a pipe by a windmill, work is accomplished.

The density of glycerin is 1.26grams/centimeter cubed . how many is this? use the conversion rates of and . express your answer to the correct number of significant figures.

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.

Calculate the energy required to ionize a hydrogen atom to an excited state where the electron is initially in the n = 5 energy level. report your answer in kilojoules