Geological evidence shows that the great barrier reef began growing over 25 years ago.
a. hundred
b. thousand
c. million
d. dozen

If equal masses of the listed metals were collected , which would have a greatest volume ? a. aluminum 2.70,b. zinc7.14,c. copper 8.92,d. lead 11.34

What is the maximum amount of al2(so4)3 which could be formed from 15.84 g of al and 12.89 g of cuso4?

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