Question

300 g of water at 25oC is added to 100 g of ice at 0oC. The final temperature of the mixture is

Solution

Correct option is

0oC

 

Let the temperature of the mixture be toC. Heat lost by water in calories

                        

Heat in calories required to melt 100 g of ice

                        

Now        Heat lost = Heat gained

Or        7500 – 300t = 8000

Or                         oC

Since t is negative, the water at 25oC cools to 0oC and melts a part of ice at 0oC.

 .

Hence only a part of the ice melts and resulting temperature is 0oC.

SIMILAR QUESTIONS

Q1

When a solid metallic sphere is heated, the largest percentage increase occurs in its

Q2

A steel scale measures the length of a copper rod as L cm when both are at 20oC, the calibration temperature for the scale. If the coefficient of linear expansion for steel and copper are  respectively, what would be the scale reading (in cm) when both are at 21oC?

Q3

At 40oC, a brass rod has a length 50 cm and a diameter 3.0 mm. It is joined to a steel rod of the same length and diameter at the same temperature. What is the change in the length of the composite rod when it is heated to 240oC? The coefficient of linear expansion of brass and steel are respectively.

Q4

A metallic container is completely filled with a liquid. The coefficient of linear expansion of the metal is  per oC and the coefficient of cubical expansion of the liquid is  per oC. On heating the vessel,

Q5

A thin metal square plate has length l. When it is heated from 0oC to 100oC, its length increases by 1%. What is the percentage increase in the area of the plate?

Q6

A glass flask of volume 500 cm3 is completely filled with a liquid at 0oC. When it is placed in boiling water at 100oC, 75 cm3 of the liquid overflows. If the coefficient of cubical expansion of glass is  oC-1, what is the coefficient of cubical expansion of the liquid?

Q7

A thin metal square plate has length l. When it is heated from 0oC to 100oC, its length increases by 1%. What is the percentage increase in the area of the plate?

Q8

The density of a liquid of coefficient of cubical expansion . When the liquid is heated to a temperature T, the change in density will be

Q9

Two rods of different materials having coefficient of thermal expansion  and Young’s modulii Y1 and Y2 are fixed between two rigid and massive walls. The rods are heated to the same temperature. If there is no bending of the rods, the thermal stresses developed in them are equal provided

Q10

100 g of ice at 0oC is mixed with 100 g of water 80oC. The final temperature of the mixture will be