Final answer:
At an atmospheric pressure of 53 kPa, water will boil at a temperature lower than what it would at 67 kPa, where water boils at 80°C. The closest appropriate answer given the options is 83°C. (Option b)
Step-by-step explanation:
The student asked at what temperature water will boil at the peak of a mountain where the atmospheric pressure is 53 kPa. The boiling point of water can be determined by the atmospheric pressure; the lower the pressure, the lower the temperature at which water will boil.
Using the information provided, one can refer to a vapor pressure curve or boiling point chart. Based on similar data, water boils at approximately 80°C at a location where the atmospheric pressure is 67 kPa. As 53 kPa is significantly lower than 67 kPa, we can infer that the boiling point would be lower than 80°C. Therefore, the correct answer is 83°C, which is option b.