You have a cup of tea (250 mL) that is 375 K which is too hot to drink. It needs to be cooled to 350 K before you can drink it. How much thermal energy has to be transferred from the tea to the surroundings to cool the tea?
Is it 63.7 thermal energy
thermal energy = q joules = mass H2O x specific heat H2O x delta T.
mass H2O is 250 grams. Specific heat H2O = 4.284 Joules. delta T is 25 C.
Plug and chug.
To determine the amount of thermal energy that needs to be transferred from the tea to the surroundings to cool it, we can use the equation:
ΔQ = m * c * ΔT
Where:
ΔQ = thermal energy transferred
m = mass of the tea
c = specific heat capacity of the tea
ΔT = change in temperature
Let's assume the specific heat capacity of tea is similar to water, which is approximately 4.18 J/g°C.
First, we need to convert the volume of the tea (250 mL) to its mass using the density of water (which is close to the density of tea), which is approximately 1 g/mL:
Mass of the tea = Volume of the tea * Density of water
Mass of the tea = 250 mL * 1 g/mL
Mass of the tea = 250 g
Next, calculate the change in temperature (ΔT):
ΔT = Final temperature - Initial temperature
ΔT = 350 K - 375 K
ΔT = -25 K
Now, we can substitute the values into the equation to find the thermal energy transferred (ΔQ):
ΔQ = m * c * ΔT
ΔQ = 250 g * 4.18 J/g°C * -25 K
ΔQ = -26125 J
Since the thermal energy transferred should be positive, we take the absolute value to obtain:
|ΔQ| = 26125 J
Therefore, the amount of thermal energy that needs to be transferred from the tea to the surroundings to cool the tea is approximately 26125 J.