Question

Three students X,Y and Z,heat water till it begins to boil and notice the temperature after it starts boiling after every 4 minutes
.
.
.
A. Which student is taking correct observation
B.Write down the observation
C.Give reason for the correct observation ​

Answer 1

Answer: z

Because water boils at 100 degrees

Explanation:

Answer 2

The correct set of observations is being taken by the student 'Z'.

A. Among X, Y, and Z, student 'Z' is recording the correct sequence of observations.

B. The observations noted down by 'Z' are :

1 - 100 °C

2 - 100 °C

3 - 100 °C

4 - 100 °C

C. • It has been said that the students started taking observations after the water began to boil. The boiling point of water is 100°C. Therefore, the first temperature noted down should be 100°C. Since the first temperature noted down by X is 80°C, his observation is incorrect.

• Now, after the water reaches the boiling point, the further heat supplied to it is used up in weakening the intermolecular forces of attraction between the water molecules to change it into vapour phase, and not to increase the temperature of water further.

• Since Y notes down temperatures in an increasing order, his observations become incorrect.

• We see that Z is the only student who notes down temperature of the boiling water as 100 °C after every 4 minutes. Therefore, his observations are correct.