Question

An unknown metal of mass $192\, g$ heated to a temperature of $100^{\circ}C$ was immersed into a brass calorimeter of mass $128\, g$ containing $240\, g$ of water a temperature of $8.4^{\circ}C$ Calculate the specific heat of the unknown metal if water temperature stabilizes at $21.5^{\circ}C$ (Specific heat of brass is $394\, J \; kg^{-1} \; K^{-1}$)

• A. $1232 \; J \; kg^{-1} \; K^{-1}$
• B. $458\; J \; kg^{-1} \; K^{-1}$
• C. $654\; J \; kg^{-1} \; K^{-1}$
• D. $916 \; J \; kg^{-1} \; K^{-1}$

Answer 1

Answer: (D)

$192 \times S \times (100 - 21.5)$
$= 128 \times 394 \times (21.5 - 8.4)$
$+ 240 \times 4200 \times (21.5 - 8.4)$
$\Rightarrow \; S = 916$