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Calculate how much heat is required, in Joules, to lower the temperature of a 0.695 g sample of iron from 45.9 ℃ to 22.7 ℃. The specific heat capacity of solid iron at constant pressure is 0.442 J / g • ℃.

User Ivan Ruski
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1 Answer

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Answer:

To calculate the amount of heat required to lower the temperature of a sample of iron, we can use the equation:

q = m * c * ΔT

where:

q is the heat (in Joules),

m is the mass of the sample (in grams),

c is the specific heat capacity of iron (in J/g • ℃), and

ΔT is the change in temperature (in ℃).

Given:

m = 0.695 g

c = 0.442 J/g • ℃

ΔT = (22.7 ℃ - 45.9 ℃) = -23.2 ℃ (Note: We use a negative sign to indicate a decrease in temperature)

Plugging in the values into the equation, we have:

q = 0.695 g * 0.442 J/g • ℃ * (-23.2 ℃)

Calculating this expression, we get:

q ≈ -7.085 Joules

Therefore, approximately 7.085 Joules of heat is required to lower the temperature of the 0.695 g sample of iron from 45.9 ℃ to 22.7 ℃.

User Homer White
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