To determine the melting point of ice

Aim

To determine the melting point of ice.

Material Required

A beaker, crushed ice, thermometer, a vertical stand.

Theory

The change of solid state to liquid state at a constant temperature by absorbing heat is called melting. This constant temperature is called melting point of that solid. Ice melts at 0°C i.e. the melting point of ice is 0°C.

Procedure

1. Clean the beaker. Fill the beaker half with the crushed ice. Place the beaker on the bottom of the stand.
2. Suspend the thermometer vertically in the beaker such that its bulb is well inside the crushed ice. Clamp the thermometer on the vertical stand as shown in the image.
3. Observe the level of mercury in the thermometer which gradually falls down.
4. When level of mercury in thermometer becomes steady and remains constant for about 1 minute, you will notice that the ice begins to melt. Note the reading of thermometer by keeping your eye horizontal in level of mercury. This will give the melting point of ice.

Observation

The constant temperature at which ice melts = 0°C.

Result

The melting point of ice = 0°C.

Precautions

1. The bulb of thermometer must not touch the base or walls of the beaker.
2. The bulb of thermometer must remain immersed inside the crushed ice.
3. The temperature must be recorded only when it becomes steady.

Viva Questions and Answers

Question-1: What is your experiment ?

Answer: To determine the melting point of ice.

Question-2: What do you mean by boiling ?

Answer: The change of state from liquid to vapours without change in temperature on absorption of heat, is called boiling.

Question-3: What is the boiling point of water ?

Answer: The boiling point of water is 100°C.