Question

Ordinary water boils at 100 degree celsius. can it be made to boil at 98 degree celsius or 103 degree celsius.

Answer 1

• There is a possibility. The pressure exerted on a liquid determines its boiling point. Under one atmosphere of pressure, water boils at 100°C. Water will boil at temperatures lower than 100°C if there is less than 1 atmosphere of pressure pressing on it. In contrast, water will boil at a temperature greater than 100°C if there is more than one atmosphere of pressure acting on it. As a result, water may be forced to boil at 98°C by lowering pressure below one atmosphere or at 103°C by increasing pressure above one atmosphere.

• Generally addition or dissolution of impurities increases the boiling point of water as it decreases the number of water molecules available to be vaporized during boiling. Hence it would take greater time to vaporize impure solution rather than pure solution, thereby increasing the boiling point.