Olympic cyclists fill their tires with helium to make them lighter. Calculate the mass of air in an air-filled tire and the mass of helium in a helium-filled tire. Assume the volume of the tire is 855 mL that is filled with a total pressure of 125 psi, and that the temperature is 25oC. Also, assume an average molar mass for air of 28.8 g/mol.

Which of the following is a compound? a.carbon b.oxygen c.hydrogen d.water

Two metal blocks that have slightly different temperatures are placed next to one another. after five minutes, they both have lower but equal temperatures. according to the law of conservation of energy, what  most likelyhappened? energy was created inside the blocks.energy was destroyed inside the blocks.energy was absorbed into the blocks from outside the system.energy was transferred from the warmer block to the cooler block.

Areaction in which products can react to re-form reactants is