Which subatomic particles takes up most of the space of an atom

Although respiratory organs vary across different organisms, they all contain respiratory surfaces that have a large surface area and are extremely thin. explain why having an extremely thin respiratory surface with a large surface area is advantageous for the process of gas exchange

Give one example of a pure (exact) number and of an estimated (measured) number.

Which is not true regarding reaction rates? (2 points) catalysts are not used up in the reaction. catalysts speed up reactions by lowering the activation energy. reaction rates decrease as the concentration of reactants decrease. during reactions, concentrations of all reactants decrease at the same rate.