the s.p.h of iron is 0.405 J/g-K. how many joules of heat are needed to raise the temperature of 0.105 kg of Fe from 298K to 361.5K
mass x specific heat Fe x delta T. Don't forget to change kg Fe to g.
Post your work if you get stuck.
(105g)(0.405J/g-K)(361.5K-298K).
(105g)(0.405J/g-K)(63.5K)=2700.33J
That looks ok to me. If your prof is picky about significant figures in the answer you need to make sure you have them right. I don't think you will be allowed all of those in your answer.
To find the amount of heat needed to raise the temperature, you can use the formula:
Q = m * c * ΔT
Where:
Q is the amount of heat (in joules),
m is the mass of the substance (in kilograms),
c is the specific heat capacity of the substance (in joules per gram-Kelvin), and
ΔT is the change in temperature (in Kelvin).
Now, we need to convert the given values to the appropriate units before plugging them into the formula.
Given:
Specific heat capacity of iron (c) = 0.405 J/g-K
Mass of the iron (m) = 0.105 kg
Initial temperature (T1) = 298 K
Final temperature (T2) = 361.5 K
First, let's convert the mass to grams:
0.105 kg x 1000 g/kg = 105 g
Next, let's calculate ΔT:
ΔT = T2 - T1
ΔT = 361.5 K - 298 K
ΔT = 63.5 K
Now, we can plug the values into the formula:
Q = m * c * ΔT
Q = 105 g * 0.405 J/g-K * 63.5 K
To simplify the units, let's convert the grams (g) to kilograms (kg):
105 g x 1 kg/1000 g = 0.105 kg
Q = 0.105 kg * 0.405 J/g-K * 63.5 K
Now, calculate the value of Q:
Q = 2.741 J
Therefore, the amount of heat needed to raise the temperature of 0.105 kg of iron from 298 K to 361.5 K is 2.741 joules.