When a chemical reaction occurs with only one substance, what happens to the atoms of that substance?

How many grams of co(g) are there in 74.5 ml of the gas at 0.933 atm and 30o c?

Word equation for k+ h2o yield koh + h2

Athe top of a hill, an athlete on a skateboard has x joules of mechanical energy. how much mechanical energy will she have at the bottom of the hill? ignore the effects of friction.