a 101 g piece of aluminum (aluminum = 0.900 J/g oC) is heated to 100.1 oC and added to 48.9 g of water at an initial temperature of 16.5oC. what will the final temperature of the mixture be

Respuesta :

Answer:

The final temperature of the mixture is = 42.14 °C

Explanation:

Mass of the aluminium [tex]m_{a}[/tex] = 101 gm

Specific heat for aluminium [tex]C_{a}[/tex] = 0.9 [tex]\frac{J}{gm c }[/tex]

Temperature of aluminium [tex]T_{a}[/tex] = 100.1 °C

Mass of water [tex]m_{w}[/tex] = 48.9 gm

Specific heat for water [tex]C_{w}[/tex] = 4.2 [tex]\frac{J}{gm c }[/tex]

Initial temperature of water [tex]T_{w}[/tex] = 16.5 °C

From energy balance principal when the aluminium piece is heated and dropped in to the water , the final temperature of aluminium & the water becomes equal.

From the energy conservation principal

Heat lost from the aluminium piece = heat gain by the water

⇒  [tex]m_{a}[/tex] [tex]C_{a}[/tex] ( [tex]T_{a}[/tex] - [tex]T_{f}[/tex] ) =  [tex]m_{w}[/tex] [tex]C_{w}[/tex] ( [tex]T_{f}[/tex] - [tex]T_{w}[/tex] ) ----------- (1)

Put all the values in equation (1)

⇒ 101 × 0.9 × (100.1 - [tex]T_{f}[/tex] ) = 48.9 × 4.2 × ( [tex]T_{f}[/tex] - 16.5 )

⇒ 90.9 × (100.1 - [tex]T_{f}[/tex] ) = 205.38 × ( [tex]T_{f}[/tex] - 16.5 )

⇒ 100.1 - [tex]T_{f}[/tex] = 2.26 ( [tex]T_{f}[/tex] - 16.5 )

⇒ 100.1 - [tex]T_{f}[/tex] = 2.26 [tex]T_{f}[/tex]  - 37.28

⇒ 3.26 [tex]T_{f}[/tex] = 137.38

[tex]T_{f}[/tex] = 42.14 °C

Therefore the final temperature of the mixture is = 42.14 °C