oxygen
It is different for every liquid. For water it is 100C
Neon is a monatomic gas, it dissovles slightly in water but causes no change to the pH as it is completely inert.
A liquid changes into a gas when it is heated to a certain temperature, known as the boiling point. Every substance has a different boiling point.
Boiling - when the liquid is heated to a gas. Evaporating - when the air temperature is hotter than the surface of the liquid so the water turns into water vapor or a gas.
A substance's boiling point is the temperature at which it changes from a liquid to a gas.
nitogen
Any liquid will change into a gas at a sufficiently high temperature. Every substance has a boiling point.
Nothing means the absence of every state (solid liquid etc...) Nothing means the absence of every stage, i.e. solid, liquid and gas. Nothing mean a vacume.
Solid
gas
All forms of matter have the three basic forms of solid - liquid - gas. Therefore, every solid can eventually be formed into a liquid by heating it up.
evaporation solid to liquid - melting liquid to gas - evaporation gas to liquid - condensation liquid to solid - freezing solid to gas and gas to solid - sublimation