Calculate the final temperature of 34mL of ethanol initially at 13∘C upon absorption of 938J of heat. (density of ethanol =0.789 g/mL)
To calculate the final temperature of the ethanol, we can use the formula:
Q = mcΔT
where Q is the heat absorbed, m is the mass of the substance, c is the specific heat capacity, and ΔT is the change in temperature.
First, let's calculate the mass of the ethanol using the given density:
mass = volume × density
mass = 34 mL × 0.789 g/mL
mass = 26.826 g
Next, we need to convert the mass of ethanol from grams to kilograms, as specific heat capacity is usually given in J/(g·K):
mass = 26.826 g ÷ 1000
mass = 0.026826 kg
Now let's rearrange the formula to solve for the change in temperature (ΔT):
ΔT = Q ÷ (mc)
Given Q = 938 J, m = 0.026826 kg, and c is the specific heat capacity of ethanol, which is approximately 2.44 J/(g·K) or 2.44 J/(mL·K). Let's use the value in J/(g·K):
ΔT = 938 J ÷ (0.026826 kg × 2.44 J/(g·K))
ΔT = 938 J ÷ 0.06556744 J/K
ΔT ≈ 14305.5 K
Since we are given the initial temperature as 13∘C, we need to convert it to Kelvin:
T_initial = 13∘C + 273.15
T_initial ≈ 286.15 K
Finally, we can calculate the final temperature by adding the change in temperature to the initial temperature:
T_final = T_initial + ΔT
T_final ≈ 286.15 K + 14305.5 K
T_final ≈ 14591.65 K
Therefore, the final temperature of the ethanol, upon absorption of 938 J of heat, is approximately 14591.65 K.
q = mass ethanol x specific heat ethanol x (Tfinal-Tinitial)
q is 938 J. mass you get from the density and volume. You must look up the specific heat of ethanol. Solve for Tfinal.