For each of the following equations, write the chemical formulas and balance the equation. Try to indicate all the physical states (solid, liquid, gas) as well.
a) potassium + water → potassium hydroxide + hydrogen
b) potassium hydride + water → potassium hydroxide + hydrogen
c) silicon dioxide + carbon → silicon carbide + carbon monoxide
d) silicon dioxide + hydrogen fluoride → silicon tetrafluoride + water
e) phosphorus + chlorine → phosphorous tetrachloride