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When 34.9 g of a metal is cooled from 225°C to 22°C, 1700 J of energy is given off. What type of metal is it?

A. Refer to the notes for the specific heat table
B. Aluminum
C. Copper
D. Iron

1 Answer

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Final answer:

The unknown metal, with a specific heat capacity of approximately 0.24 J/g°C deduced from the heat loss of 1700 J while cooling from 225°C to 22°C, is most likely copper, which has a specific heat close to 0.39 J/g°C.

Step-by-step explanation:

To determine the identity of the metal based on the given information, we can use the formula for heat transfer:
Q = m × c × ΔT

Where:

  • Q is the energy in joules (J)
  • m is the mass in grams (g)
  • c is the specific heat capacity (J/g°C)
  • ΔT is the change in temperature (°C)

Given:

  • Q = -1700 J (negative because energy is given off)
  • m = 34.9 g
  • ΔT = 225°C - 22°C = 203°C

We can solve for the specific heat capacity c:
c = -Q / (m × ΔT)

c = 1700 J / (34.9 g × 203°C)

c = 1700 J / (7085.7 g°C)

c = 0.24 J/g°C (approx.)

Comparing this value with standard specific heat capacities, we find that the closest match is copper with a specific heat capacity of approximately 0.39 J/g°C. Therefore, the unknown metal is most likely copper.

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