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How many grams of carbon are present if it requires 57.5 kJ of energy to heat a sample

from 20.0 to 25.0°C?

User Sguan
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1 Answer

3 votes

Answer:

Step-by-step explanation:

The amount of heat (q) required to raise the temperature of a substance is given by:

q = mcΔT

where m is the mass of the substance, c is the specific heat capacity of the substance, and ΔT is the change in temperature.

To find the mass of carbon present, we need to rearrange the formula as follows:

m = q / (cΔT)

We are given the following information:

q = 57.5 kJ (the amount of heat required)

ΔT = 25.0°C - 20.0°C = 5.0°C (the change in temperature)

The specific heat capacity of carbon is approximately 0.71 J/g°C.

We need to convert the amount of heat from kJ to J:

q = 57.5 kJ * 1000 J/kJ = 57500 J

Now we can substitute the values into the formula and solve for m:

m = q / (cΔT) = 57500 J / (0.71 J/g°C * 5.0°C) ≈ 1620 g

Therefore, approximately 1620 grams of carbon are present.

User Mantal
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