Question

Which one of the following would raise the temperature of 20 gm of water at 30⁰C most when mixed with :

• A. 20 gm of water at 40⁰C
• B. 40 gm of water at 35⁰
• C. 10 gm of water at 50⁰C
• D. 4 gm of water at 80⁰C

Answer 1

Answer: (D)

4 gm of water at 80⁰C

Answer 2

T = $\frac{m_{1}s_{1}T_{1} + m_{2}s_{2}T_{2}}{m_{1}s_{1} + m_{2}s_{2}}$,

T is maximum, If we take 4 gm of water at 80⁰C