You combine 212.56 grams of hydrogen gas with 600.086 grams of oxygen. What would be the mass of the resulting material after the chemical reaction has taken place?

Which of the following is a testable hypothesis? a. if i brush my teeth, i will get fewer cavities than if i don't brush my teeth. b. green toothpaste tastes better than blue toothpaste or red toothpaste. c. smart, careful, healthy people always brush their teeth. d. it's wrong to not brush your teeth before you have an important conversation with someone.

The enthalpy of formation of water is -285.8 kj/mol. what can be inferred from this statement?

Joseph has hypothesized that sound travels in waves. if he were following the scientific method, what should he do next? a. ask a question. b. test the hypothesis. c. study the results. d. tell other scientists about his hypothesis.