The specific heat of copper metal is 0.385 J/ g- K. How many KJ of heat needed to raise the temperature of 1.1 kg block of copper from 27.5 C to 50 C?
Heat=mass*specHeat*changeinTemp
Notice you are given specific heat in J/gK. the same value applies with units kJ/kg-K
To find the amount of heat needed to raise the temperature of the copper block, we can use the equation:
Q = m * c * ΔT
Where:
Q = heat energy (in Joules)
m = mass of the copper block (in kilograms)
c = specific heat of copper (in J/g-K)
ΔT = change in temperature (in Kelvin)
First, let's convert the mass of the copper block to grams:
1.1 kg = 1100 g
Next, let's calculate the change in temperature in Kelvin:
ΔT = 50 C - 27.5 C = 22.5 K
Now, we can solve for the heat energy (Q):
Q = 1100 g * 0.385 J/g-K * 22.5 K
Calculating this expression will give us the heat energy in Joules. However, the question asks for the answer in Kilojoules, so we need to convert from joules to kilojoules.
1 kilojoule = 1000 joules
Let's carry out the calculation:
Q = 1100 g * 0.385 J/g-K * 22.5 K
Q = 9,075 J
Converting to kilojoules:
Q = 9,075 J / 1000
Q = 9.075 kJ
Therefore, the amount of heat needed to raise the temperature of the 1.1 kg block of copper from 27.5 C to 50 C is approximately 9.075 kJ.
To calculate the amount of heat energy needed to raise the temperature of a substance, you can use the formula:
Q = m * c * ΔT
Where:
Q is the heat energy
m is the mass of the substance
c is the specific heat capacity of the substance
ΔT is the change in temperature
Given data:
Specific heat of copper (c) = 0.385 J/g-K
Mass of copper (m) = 1.1 kg
Change in temperature (ΔT) = 50°C - 27.5°C = 22.5°C
Now, let's convert the units so that they are consistent:
We'll convert the mass from grams (g) to kilograms (kg):
1.1 kg * 1000 g/kg = 1100 g
The specific heat capacity (c) is in J/g-K, so we need to convert it to J/kg-K:
0.385 J/g-K * (1 kg / 1000 g) = 0.385 J/kg-K
Now we can substitute these values into the formula:
Q = m * c * ΔT
= 1100 g * 0.385 J/kg-K * 22.5 K
= 9697.5 J
Finally, let's convert the answer from joules (J) to kilojoules (kJ):
9697.5 J * (1 kJ / 1000 J) = 9.6975 kJ
Therefore, the heat needed to raise the temperature of a 1.1 kg block of copper from 27.5°C to 50°C is approximately 9.7 kJ.