How did thomson know atoms had an overall neutral charge? he knew there were negative electrons but he came to the conclusion that the rest of the atom was positively charged, why was this? how did he know it would be positively charged?

Why does karst topography exist in some geographic location? a. few climates have enough oxygen b. most regions have rock layers other than limestone c. in most regions, the soil is too thin d. the water is too acidic enough in most places

What ia the energy of an object because of its potential and kinetic energies

Which best term to describe a chemical reaction that absorbs energy from its surroundings? a.thermal conductor b.thermal insulator c.endothermic d.exothermic