1125 J of energy is used to heat 250 g of iron. After heating, the final temperature of the iron is measured as 55 °C. The specific heat capacity of iron is 0.45 J/(g·°C).
What was the initial temperature of the iron?
This is exactly the same kind of problem I did for you yesterday. Work this one the same way.
To determine the initial temperature of the iron, you can use the equation:
Q = m * c * ΔT
Where:
Q is the amount of heat energy absorbed (in Joules)
m is the mass of the substance (in grams)
c is the specific heat capacity of the substance (in J/(g·°C))
ΔT is the change in temperature (in °C)
In this case, you have:
Q = 1125 J
m = 250 g
c = 0.45 J/(g·°C)
ΔT = (final temperature) - (initial temperature)
Since you want to find the initial temperature, the final temperature is known as 55 °C.
Let's plug in the values into the equation and solve for the initial temperature (T_initial):
1125 J = 250 g * 0.45 J/(g·°C) * (55 °C - T_initial)
First, simplify:
1125 J = 112.5 (55 °C - T_initial)
Then, divide both sides by 112.5:
1125 J / 112.5 = 55 °C - T_initial
10 = 55 °C - T_initial
Next, rearrange the equation:
T_initial = 55 °C - 10
T_initial = 45 °C
Therefore, the initial temperature of the iron is 45 °C.