Please explain how the potential and kinetic energies of the firework are changing, and what is happening to the total mechanical energy of the firework.

Describe what happens to the molecules as water goes from ice to liquid to vapor. be sure to explain what happens to the temperature during the phase changes.

Ariver current has a velocity of 5km/h relative to the shore, and a boat moves in the same direction as the current at 5 km/h relative to the river. how can the velocity of the boat relative to the shore be calculated?

Butane gas reacts with oxygen gas to give carbon dioxide gas and water vapor (gas). if you mix butane and oxygen in the correct stoichiometric ratio, and if the total pressure of the mixture is 390 mmhg, what is the pressure (in mmhg) of water vapor after the reaction is completed (temperature and volume do not change).