Propane is used as a fuel, commonly in portable grills. If 15.0 grams of propane are burned in the presence of 15.0 grams oxygen, what mass of carbon dioxide should be expected? Show work please.

C3H8 + 5O2 → 4H2O+ 3CO2

24. a sports ball is inflated to an internal pressure of 1.85 atm at room temperature (25 °c). if the ball is then played with outside where the temperature is 7.5 °c, what will be the new pressure of the ball? assume the ball does not change in volume nor does any air leak from the ball a) 0.555 atm b) 1.74 atm c) 1.85 atm d) 1.97 atm

Can someone me with 3 and 4 plz. this is for masteries test.

Astudent is trying to create a table that compares hypotheses, theories, and laws. hypothesis theory law do scientific researchers formulate it? yes yes yes does it explain why things happen? yes yes no yes yes yes is it used to make predictions? no yes yes which of the following questions would most likely fill the blank in the table? is it an intelligent guess? is it newly formulated? is it based on observations? has it been proved?