Are temperature and pressure the ONLY factors that affect the state of water?

Answer 1

No. A study was done by a japanese physicist that proved that the actual molecular structure of water changes as a reaction to the emotional environment around it.

For example, a happy environment causes the molecules to form beautiful snowflake-like shapes. While, an angry environment will cause it to look very jagged and forboding.

I know that sounds pretty crazy, but there's proof of it. And nobody knows why that is.

Answer 2

From the source, these are the factors affecting the state of water:

~Depth: m
Pressure: dbar
Temperature: deg C
Conductivity: S/m
Salinity: PSU
Density: kg/m^3

Depth and pressure are just two manifestations of the same thing because pressure can be derived from depth. There is also correlation among the bottom four factors; so any two of these last four, along with any one of the first two, can be used to determine the state of water. [See source.]

Answer 3

If you are talking about pure water and state meaning solid, liquid or gas, then yes. But if you water is not pure, then this also has an effect, for example when you add salt to water, its melting point is lowered - I.e. That's why in winter if you throw salt on your driveway it melts the ice.