j 2006 4- evaporation can happen at any temp. for boiling u need to reach the boiling point e.g water boils at 100c but it can evaporate at any temp, like room temp. how pressure affects, not sure but i will try. evaporation at any temp, means pressure can be differet, boiling for water at 100c, more pressure (in gas laws, when temp increase, pressure increase) one more point, during boiling temp doesn't change, means pressure is constant