1125 J of energy is used to heat 250 g of iron to 55 °C. The specific heat capacity of iron is 0.45 J/(g·°C).
What was the temperature of the iron before it was heated?
55 °C
35 °C
20 °C
45 °C
Not sure how to solve this problem, can anyone walk me through it?
Never mind- I figured it out.
The answer is 45
q = mass x specific heat Fe x (Tfinal-Tinitial)\
1125 J = 250 x 0.45 J/g*C x (55 - Tinitial)
Solve for Tinitial
Post your work if you get stuck.
To solve this problem, we can use the formula:
Q = mcΔT
Where:
Q = amount of heat absorbed or released
m = mass
c = specific heat capacity
ΔT = change in temperature
In this case, we are given:
Q = 1125 J
m = 250 g
c = 0.45 J/(g·°C)
ΔT = 55 °C
We want to find the initial temperature (T1) before the iron was heated.
Rearranging the formula, we have:
Q = mcΔT
Q = mc(T2 - T1)
Plug in the given values:
1125 J = (250 g)(0.45 J/(g·°C))(55 °C - T1)
Now, we can solve for T1:
1125 J = (250 g)(0.45 J/(g·°C))(55 °C - T1)
Divide both sides of the equation by (250 g)(0.45 J/(g·°C)):
1125 J / (250 g)(0.45 J/(g·°C)) = 55 °C - T1
Now, calculate the left side of the equation:
1125 J / (250 g)(0.45 J/(g·°C)) ≈ 10
Substitute this value back into the equation:
10 ≈ 55 °C - T1
Now, solve for T1:
T1 ≈ 55 °C - 10
T1 ≈ 45 °C
Therefore, the temperature of the iron before it was heated is approximately 45 °C.