How does the temperature of water affect how fast sugar can dissolve?

Predict
We will do three different tests, dissolving the water in boiling, warm and cool water. The sugar in the boiling water will dissolve the fastest. The sugar added to the cool water will dissolve the slowest.

Reason
According to the state of matter theory, the particles in a gas move faster than in a liquid, which I will use to infer that the hotter the water is and closer to a gas, the faster the particles move. Therefore when sugar is added to the boiling water it will break down faster as the particles are moving more quickly and will collide with the sugar which will bond with the water and therefore dissolve or break it down. As the cooler water has slower moving particles, it will take longer for them to collide with the sugar and break it down.

Observe
In order to conduct the experiment and test the hypothesis, three experiments were conducted using boiling water, hot water (tap on hot) and cold water (tap on cold). Half a cup of water was used for each experiment, to which 1 teaspoon of white sugar was added and then stirred until dissolved. Diagram of the setup showing 1/2 cup of water and a one teaspoon measuring spoon.

Boiling water- The sugar added to the boiling water began to instantly dissolve, taking 7 seconds to completely disappear.

Warm Water- The added sugar sank to the bottom of the cup. As I began to stir, the sugar granules appeared to shrink in size and become more transparent before finally disappearing. This process took 25 seconds.

Cool Water- Once again the sugar sank straight to the bottom. When stirred, the sugar began to visibly break down, however this process was slower than in the warm water. The sugar took 45 seconds to completely dissolve.

Explain
The prediction was correct as the sugar dissolved the fastest in the boiled water. However the cause of this is more detailed than the one suggested. Sugar is a molecule called sucrose, a combination of carbon, hydrogen and
oxygen atoms. The crystals which give white sugar its appearance are arrangements of these sucrose molecules which are bonded together by hydrogen (What is sugar?, 2011).

The particle theory dictates that all matter is made up of tiny particles which are in a constant state of motion. The speed of the particles is dictated by temperature, with an increase resulting in faster moving particles (The Particle Theory, 2012). To dissolve the sugar, the particles in the water are attracted to the sucrose molecules and surround and bond with them, which produces energy. This disrupts the structure of both the water and the sugar and allows the carbon, hydrogen and oxygen atoms to be released into the solution and the solute to be dissolved (Bodner Research Web, 2006). When heat is added, the particles in the water move faster, creating more energy and breaking the bonds faster which increases the rate at which the sugar dissolves. Therefore the prediction was correct in saying the sugar in the boiling water would dissolve the fastest as the faster moving particles in the water dissolve the bonds of the sugar.

The investigation was fair, as all dependent variables were kept the same, including the same amount of water and sugar, same sugar type used and over a small time frame to ensure the room temperature was kept approximately the same. The accuracy of the results could be improved by increasing the sample size, to enable more tests and more data to be collected to find a more accurate dissolving rate. A different type of sugar could be used to allow the sugar to be more easily seen in the cup and more clearly observe the breaking down and dissolving of the sugar.

Future experiment
Does the temperature affect the saturation point of a liquid? This experiment would involve testing how many teaspoons of sugar can dissolve in a cool and boiled water solution. This would provide further knowledge on how heat can speed up the particles and what effect this has. It would also be interesting to see how the dissolving rate changes when different types of sugar are used.

References
Bodner Research Web. (2006). Solubility. Retrieved April 3, 2012, from Purdue
Univeristy: Division of Chemcial Education: chemed.chem.purdue.edu/genchem/topicreview/bp/ch18/soluable.php
Frangenehim, E. (2007). Reflections on classroom thinking strategies. Loganholme: Rodin Educational Publishing.
The Particle Theory. (2012). Retrieved April 3, 2012, from Click and learn: http://www.clickandlearn.org/gr9_sci/particle_theory.htm
What is sugar? (2011). Retrieved April 4, 2012, from Exploratorium: http://www.exploratorium.edu/cooking/candy/sugar.html