Questions: A 55.0 kilogram (kg) block of metal has an original temperature of 15.0°C and 0.45 J/g°C. What will be the final temperature of this metal if 75500 J of heat energy is absorbed by the metal?
Transcript text: A 55.0 kilogram ( kg ) block of metal has an original temperature of $15.0^{\circ} \mathrm{C}$ and $0.45 \frac{\mathrm{J}}{\mathrm{g}^{\circ} \mathrm{C}}$. What will be the final temperature of this metal if 75500 J of heat energy is absorbed by the metal?
Solution
Solution Steps
Step 1: Identify the given values
We are given:
Mass of the metal block, \( m = 55.0 \, \text{kg} \)
Specific heat capacity, \( c = 0.45 \, \frac{\text{J}}{\text{g}^{\circ} \text{C}} \)
Heat energy absorbed, \( Q = 75500 \, \text{J} \)
Step 2: Convert mass to grams
Since the specific heat capacity is given in \(\frac{\text{J}}{\text{g}^{\circ} \text{C}}\), we need to convert the mass from kilograms to grams:
\[ m = 55.0 \, \text{kg} \times 1000 \, \frac{\text{g}}{\text{kg}} = 55000 \, \text{g} \]
Step 3: Use the heat energy formula
The formula to calculate the change in temperature when heat energy is absorbed is:
\[ Q = mc\Delta T \]
where \(\Delta T\) is the change in temperature.
Step 4: Solve for \(\Delta T\)
Rearrange the formula to solve for \(\Delta T\):
\[ \Delta T = \frac{Q}{mc} \]
Substitute the given values:
\[ \Delta T = \frac{75500 \, \text{J}}{55000 \, \text{g} \times 0.45 \, \frac{\text{J}}{\text{g}^{\circ} \text{C}}} \]
Step 5: Calculate \(\Delta T\)
\[ \Delta T = \frac{75500}{55000 \times 0.45} \]
\[ \Delta T = \frac{75500}{24750} \]
\[ \Delta T \approx 3.051 \, ^{\circ} \text{C} \]
Step 6: Find the final temperature
The final temperature \( T_f \) is the initial temperature plus the change in temperature:
\[ T_f = T_i + \Delta T \]
\[ T_f = 15.0^{\circ} \text{C} + 3.051^{\circ} \text{C} \]
\[ T_f \approx 18.051^{\circ} \text{C} \]