Different isotopes of the same element must have a different a. mass number b. atomic number c. number of protons d. number of electrons

Ageologist determines that a sample of a mineral can't be scratched by a steel nail but can be scratched by a masonry drill bit. based on this information, the sample mineral has to be softer than a. orthoclase. b. fluorite. c. apatite. d. corundum.

Consider this initial-rate data at a certain temperature for the reaction described by

When a septic tank backs up a goes in to clean it out