Question

Joyce poured 200 milliliters (mL) of water into a beaker, placed a thermometer in it, and heated it until it started to boil. She recorded a temperature of 100 degrees Celsius (°C) when it started to boil. She repeated the process with 400 mL of water. What would be the temperature when this second sample started to boil?

a) The same as the first sample's
b) Half as high as the first sample's
c) Twice as high as the first sample's
d) Slightly higher than the first sample's

Answer 1

The second sample of water would start to boil at 100 degrees Celsius, a) the same as the first sample, because the boiling point of a substance is a characteristic property that does not change with the amount of substance if the pressure remains constant.

Step-by-step explanation:

The temperature when the second sample of water started to boil would be a) the same as the first sample's boiling temperature. The boiling point of a substance on the Celsius scale is a characteristic property, meaning it does not change with the amount of the substance if the pressure remains constant. In this case, since both experiments are presumably conducted at the same atmospheric pressure, the 400 mL of water would also start to boil at 100 degrees Celsius. The boiling point of water is influenced by atmospheric pressure, not the volume of water being boiled. Only changes in pressure, the addition of solutes, or impurities can change the boiling point. In Joyce's experiments, she has the same conditions for both volumes of water; therefore, the boiling point remains constant regardless of the increase from 200 mL to 400 mL of water.