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How much energy is needed to increase the temperature of 755g of iron from 283k to 403k ?

User Geekydel
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2 Answers

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Final answer:

To find the energy needed to increase the temperature of 755 g of iron from 283 K to 403 K, we use the specific heat capacity of iron (0.449 J/g °C) and the formula q = mcΔT. After converting the temperatures to Celsius, the calculation shows that 40,714 joules of energy is required.

Step-by-step explanation:

The question asks how much energy is required to increase the temperature of a specific mass of iron. The calculation involves using the formula for heat energy, which is q = mcΔT. The specific heat (c) of iron, the mass (m) of the iron object, and the change in temperature (ΔT) are required to find the total amount of energy needed.

To calculate the energy needed to increase the temperature of 755 g of iron from 283 K to 403 K, we use the specific heat capacity of iron, which is given as 0.449 J/g °C in a comparable example. First, we convert the temperatures from Kelvin to Celsius by subtracting 273 from both temperatures. This gives us a starting temperature of 10 °C and an ending temperature of 130 °C. The change in temperature is then 130 °C - 10 °C = 120 °C.

Using the formula q = mcΔT, where
m = 755 g (mass of iron),
c = 0.449 J/g °C (specific heat capacity of iron),
ΔT = 120 °C (change in temperature),
we can calculate the energy required as:

q = (755 g) x (0.449 J/g °C) x (120 °C) = 40,714 J

This means that 40,714 joules of energy is needed to increase the temperature of 755 g of iron from 283 K to 403 K.

User Dmitry Katkevich
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2 votes
The amount of energy needed to increase the temperature of a substance by
\Delta T is given by:

Q=m C_s \Delta T
where
m is the mass of the substance

C_s is the specific heat capacity of the substance

\Delta T is the increase of temperature

In our problem,
m=755 g, while

\Delta T=403 K-283 K=120 K
and the specific heat capacity of iron is

C_s =0.45 J/gK

if we plug these numbers in the equation, we find the amount of energy needed:

Q=mC_s \Delta T=(755 g)(0.45 J/gK)(120 K)=4.08 \cdot 10^4 J
User Lucas Lopes
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8.6k points