A chance event such as a fire or an earthquake might change the gene pool of a population in a process know as?

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

Which statement explains why the bonds between non metals tend to be covalent? the bonds are found to be nondirectional they have large differences in electronegativity they have small differences in electronegativity they have ions that produce an electrostatic pull

Which of the following is an indication that a substance has undergone a chemical change? a. no new product has been formed. b. the color of the substance has not changed. c. the original constitute has not changed. d. the molecular structure has changed.