Discussion Forum

The temperature of equal masses of three different liquids A, B and C are 12ºC, 19ºC and 28ºC respectively. The temperature when A and B are mixed is 16ºC and when B and C are mixed is 23ºC. The temperature when A and C are mixed is

Answer:

Explanation:

Heat gain = Heat lost

C_A (16 - 12) = C_B(19 - 16) → $\frac{C_{A}}{C_{B}} = \frac{3}{4}$

and C_B (23 - 19) = C_C(28 - 23)  → $\frac{C_{B}}{C_{C}} = \frac{5}{4}$

 → $\frac{C_{A}}{C_{C}} = \frac{15}{16}$         .....(i)

If θ is the temperature when A and C are mixed then,

C_A (θ - 12) = C_C(28 - θ) → $\frac{C_{A}}{C_{C}} = \frac{28 - θ}{θ - 12}$ ....(ii)

On solving equations (i) and (ii) θ  = 20.2ºC