The density of copper is 8.9 g/mL. What is the volume of 20.5 g copper?

Both 1,2−dihydronaphthalene and 1,4−dihydronaphthalene may be selectively hydrogenated to 1,2,3,4−tetrahydronaphthalene. one of these isomers has a heat of hydrogenation of 101 kj/mol (24.1 kcal/mol), and the heat of hydrogenation of the other is 113 kj/mol (27.1 kcal/mol). match the heat of hydrogenation with the appropriate dihydronaphthalene.

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

To calculate percent by mass, use the equation below: calculate the percent by mass of each element. %n = % %h = % %o = %