To find the final temperature of the water, we can use the formula:
Q = m * C * ΔT
Where:
Q is the heat energy input (in joules),
m is the mass of the substance (in grams),
C is the specific heat capacity of the substance (in joules per gram per degree Celsius), and
ΔT is the change in temperature (in degrees Celsius).
First, we need to calculate the heat energy input Q using the given information: Q = 84 joules.
Next, we know the mass of water is 2.0 grams and the initial temperature is 15 degrees Celsius.
Lastly, we need to know the specific heat capacity of water, which is approximately 4.18 joules per gram per degree Celsius.
Now, we can solve for the change in temperature ΔT:
ΔT = Q / (m * C)
ΔT = 84 J / (2.0 g * 4.18 J/g°C)
ΔT ≈ 10.05 °C
To find the final temperature, we add the change in temperature to the initial temperature:
Final temperature = Initial temperature + ΔT
Final temperature = 15 °C + 10.05 °C
Final temperature ≈ 25.05 °C
Therefore, the answer is C. The final temperature of the water will be approximately 25 degrees Celsius.