Name: Calorimeter
Uploaded: 2019-07-19
Duration: 3 min 29 s
Description: Let's study the parts of a calorimeter and understand its functioning. Also, explore the exchange of heat that takes place when a substance of two varying te...

Question

Describe a method to find latent heat of melting of ice.

Accepted Answer

Let a piece of ice at $— 10 ° C$ is heated at a constant rate. The graph given below shows the rise in temperature of water (ice) with respect to time.

Portion OA of the graph shows continuous rise in temperature of ice. Point A indicates the ice at temperature $0 ° C$ . Portion AB of the graph shows no change in temperature for some time although flow of heat is on. Point B shows water at temperature $0 ° C$ . It means from A to B heat is given to ice at $0 ° C$ to change its phase and convert into the water at the same temperature. This heat is called latent heat of melting. When some heat is given to any body it gains temperature and when some heat is taken from the body it loses temperature. However, when a body changes its state (from solid to liquid or from liquid to gas or vice versa) heat given to body does not show any change in its temperature. This hidden heat given to the body is called the latent heat of the body. When ice at $0^{°} C$ is heated its temperature does not rise till all ice melts and converts into water at $0 ° C$ . The heat given to change the ice into water at $0 ° C$ is called latent heat of melting of ice. It is $80$ calorie per gram. Similarly if water at $0 ° C$ is cooled to convert it into ice at same temperature it is called latent heat of fusion of ice. Obviously this value is also $80$ calorie per gram. Latent heat of melting or of fusion is different for different substances. Latent heat per unit mass is also called specific latent heal and is denoted by $L$ . The value of $L$ for ice $= 80 calorie / g$ .

$L = \frac{Heat given for change of phase}{Mass} = \frac{Q}{m}$

Describe a method to find latent heat of melting of ice.

Important Questions on Calorimetry

Learn and Prepare for any exam you want !