Final answer:
The calculation provides a value of 740 m/s for the average speed of water molecules at 100.0°C based on the average speed at 25.0°C; however, this result is not among the available options, indicating an error or missing information in the question.
Therefore, the correct answer among the given options is not provided.
Step-by-step explanation:
The question asks us to calculate the average speed of water molecules at 100.0°C given their average speed at 25.0°C.
Assuming this change in temperature follows the kinetic theory of gases, the speed of the molecules would be proportional to the square root of the absolute temperature ratio:
v(T2) = v(T1) * sqrt(T2/T1)
To find the average speed at 100.0°C, one must convert Celsius to Kelvin (by adding 273.15), and then apply the formula above.
The absolute temperature at 25°C is 298.15 K and at 100°C is 373.15 K:
v(100.0°C) = 640 m/s * sqrt(373.15 / 298.15)
Calculating this gives an average speed of 740 m/s, which, rounded to the nearest whole number, is 740 m/s. However, this value is not listed in the multiple-choice options provided, which suggests there may be an error in the question or a misunderstanding of the context or constants involved.
Therefore, without additional information, we cannot determine the correct answer from the options provided.