What is the law of chemical equivalent?

Before it was launched, a helium-filled balloon had a pressure of 201 kpa at a temperature of 27°c. at an altitude of 15,000 m, the pressure had decreased to 2.5 kpa and the temperature had dropped to -14 °c. the volume of the balloon increased to 59.3 m3. what is the original volume of the balloon? 13 m3 0.85 m3 0.077 m3 1.17 m3

The density of e85 fuel is 0.801 g/ml. what is the mass of 1.00 gallon of the fuel? (1 gal. = 3.785 l)

What is matter? a. anything that has mass and takes up space b. something that has volume and takes up space. c. things that have energy and take up space d. things that take up space but don't have mass