Calculate the amount of heat required to raise the temperature of a 25 g sample of water from 9 ∘C to 30 ∘C.
Express your answer using two significant figures.
q = mass H2O x specific heat H2O x (Tfinal-Tinitial)
To calculate the amount of heat required to raise the temperature of a substance, we can use the equation:
q = m * c * ΔT
Where:
q is the amount of heat (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)
First, let's determine the heat capacity, which is the product of the mass and specific heat capacity:
m = 25 g
c = 4.18 J/g⋅°C
Now, we need to find the change in temperature (ΔT). ΔT is calculated by subtracting the initial temperature (9 °C) from the final temperature (30 °C):
ΔT = 30 °C - 9 °C = 21 °C
Now, we can substitute the values into the equation:
q = (25 g) * (4.18 J/g⋅°C) * (21 °C)
Calculating this expression:
q ≈ 2199 J
Therefore, the amount of heat required to raise the temperature of the 25 g sample of water from 9 °C to 30 °C is approximately 2199 J.