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A copper calorimeter can with mass 0.100kg contains 0.160kg of water and 0.018kg of ice in thermal equilibrium at atmospheric pressure.
Part A
If 0.750kg of lead at a temperature of 255 c is dropped into the calorimeter can, what is the final temperature? Assume that no heat is lost to the surroundings

Respuesta :

Explanation:

The given data is as follows.

  Mass of copper calorimeter, ([tex]m_{cu}[/tex]) = 0.1 kg

 specific heat of copper calorimeter, ([tex]c_{cu}[/tex]) = 390 J/kg K

  mass of water, ([tex]m_{w}[/tex]) = 0.160 kg

  specific heat of water, ([tex]c_{w}[/tex]) = 4190 J/kg K

    mass of ice, ([tex]m_i[/tex]) = 0.018 kg

latent heat of ice = [tex]334 \times 103 J/kg[/tex]

mass of lead, ([tex]m_{Pb}[/tex]) = 0.75 kg

specific heat of lead, ([tex]c_{Pb}[/tex]) = 130 J/kg K

Heat lost by the lead is

           Q = [tex]m_{pb} \times C_{Pb} \times (255 - T)[/tex]

               = [tex]0.75 \times 130 J/kg K \times (255 - T)[/tex]

                = 97.5 (255 - T)

Now, heat gained by calorimeter is calculated as follows.

        Q = [tex](m_{w} + m_{ice}) \times c_{w} \times T + m_{Cu} \times C_{Cu} \times T + m_{ice} \times L_{f}[/tex]

           = [tex](0.160 + 0.018)(4190) T + (0.1)(390 J/kg K) T + (0.018 kg )(334 \times 103)[/tex]

Hence, heat loss by lead is equal to heat gained by calorimeter .

So,      97.5 (255 - T ) = 745.82 T + 39 T + 6012

             18850.5 = 882.32 T

                 T = [tex]21.36^{o}C[/tex]

Thus, we can conclude that the value of final temperature is [tex]21.36^{o}C[/tex].