Why do scientists need to classify elements

How many electrons does silver have to give up in order to achieve a sido noble gas electron configuration

The primary products of complete combustion of fossil fuels are a. carbon dioxide and water b. methane and water c. carbon monoxide and water d. carbon dioxide and carbon monoxide

When an experimenter draws a conclusion that he assumes will apply to all situations set up similarly to his test situation, even though he cannot possibly have examined all possible test scenarios, the experimenter is using deductive reasoning inductive reasoning abductive reasoning subjective reasoning