Question

determines the specific heat of the iron if 50 g of cloves are placed in 100 ml of cold water at 10º C and 100 ml of hot water at 70º C are added.
The temperature of the mixture is 35.5ºC

Answer 1

1 L = 1000 g 1 mL = 1 g 100 mL = 100 g = m ( mass of water )

Mass of iron = M = 50 g

Specific heat of water = c_w = 4.2 J / g ^oC

Final temperature of the mixture = T = 35.5^o C

Let, the specific heat of iron be C_I in J / g ^oC and initial temperature of iron be t

Hence, according to principle of calorimetry,

Heat gained by ( iron + water ) at 10 C = Heat gained by water at 70^o C

M x C_I x ( T - t ) + m x c_w x ( T - 10 ) = m x c_w x ( 70 - T )

50 x C_I x ( 35.5 - t ) + 100 x 4.2 x ( 35.5 - 10 ) = 100 x 4.2 x ( 70-35.5 )

50 ( 35.5 - t ) C_I + 10710 = 14490

50 ( 35.5 - t ) C_I = 14490 - 10710 = 3780

( 35.5 - t ) C_I = ( 3780 / 50 ) = 75.6

Specific heat of iron = CI = 75.6 / ( 35.5 - t ), where, t = initial temperature of iron.