How does changing the surface area of a sample of water affect the time taken for the water to boil?
Background: By changing the containers of the water, the surface area of the water is thus being modified as the same volume of water is spread out over smaller or larger surfaces. The measure being compared is the time each sample of water will take before it reaches the boiling point, 100 C°. The relationship between the surface area and this amount of time will be determined by comparing the circular area of each container to the time.
The independent variable manipulated in this lab is surface area, which will be varied by filling the water into different sized containers. The dependent variable being measured is the time taken to boil in seconds. This will therein tell us the rate of boiling, a measure of the rate of vaporization. Variables that must be controlled while performing this experiment include the temperature of the water and the volume of the water.
– petri dish
– test tube
– 80 mL beaker
– 300 mL beaker
– graduated cylinder
– 5 50 mL samples of distilled water
– Bunsen burner
– metal ring stand
1. Measure in cm the radius of each the petri dish, test tube, graduated cylinder, and two beakers. Calculate the area of each. 2. Pour 50 mL of distilled water into petri dish. Repeat for test tube, graduated cylinder, 80 and 300 mL beakers. 3. Set up Bunsen burner and metal ring stand. Place petri dish with distilled water on metal ring stand. Place thermometer in petri dish. 4. Turn on gas / Bunsen burner. Start stopwatch.
5. Measure with stopwatch the time it takes until the thermometer reads 100° C (boiling point of water). Record this time. 6. Repeat steps 1 – 5 four more times. 7. Repeat above procedure using the test tube, graduated cylinder, and two beakers.