4. Discussion

Analysis of Results

Salt and Sugar
Most of the time, salt water freezes faster than sugar r wate. However, 1g of sugar started to freeze faster than 4g of salt.3g and 4g of sugar did not manage to start freezing in 3 minutes. Pure water(Control) did not manage to freeze within 3 minutes.

60 degree of water froze faster than 65 degree of water.However,both 60 degree of water and  65 degree started freezing within 3 minutes.

Explanation of Key Findings
For some temperatures, Mphema effect should have happened. Mphema effect is the effect where hotter water freezes faster than colder water. However,as there might be some unforeseen conditions, the colder water actually started to freeze earlier than the hotter water. As described by Nikola Bregović, water with the temperature of 35 degree Celsius will start to freeze earlier than water with the temperature of roughly 25 degrees.This effect can aso be seen from James D. Brownridge(2010), where he concluded that Hot water will freeze before cooler water only when the cooler water supercools, and then, only if the nucleation temperature of the cooler water is several degrees lower than that of the hot water. Heating water may lower, raise or not change the spontaneous freezing temperature.
For salt and sugar,the temperature of the water varies on the amount of salt and sugar put inside it.

Evaluation of hypothesis
For the first hypothesis, the hypothesis does work for some amounts of salt and sugar.However,it did not work for 4g of sugar.This could be because of the high amount of impurities,thus this might not have helped in the freezing of water and might actually have slowed it down.

Areas of improvement
  1. We could have experimented for a longer period of time(eg. 5mins-10mins) so that we can see how the temperature of the water will be affected even after it has frozen.
  1. We could have included repeats,so we can repeat each procedure to ensure we can have a more reliable result.
  2. We could have planned our time more effectively as we did not have much time to finish the experiment so that we can have more time to improve on different part of the report.

No comments:

Post a Comment