PHYSICAL PROPERTIES - Properties that can be observed without changing the chemical ID of the substance (cane sugar).
1. COLOR
After examining the grains of sugar, I determined that they are clear with a slight white tint. When looked at in a group of many grains, the overall color appears to be plain white. This is a physical property because I can observe it without changing the chemical ID of the sugar.
2. SOLUBILITY
I poured some of the sugar into a glass of water. At first, it just sank and sat at the bottom. However, after I stirred it, I began to see waves in the water appear and it was clear that the sugar was dissolving. In conclusion, sugar is soluble because it dissolves when put into a liquid. It does not change the substance of the sugar, though, so it is a physical property. It can also be reversed by evaporating the water.
3. CONDUCTIVITY
To measure the electrical conductivity of the sugar, I borrowed my dad's multimeter/ohm-meter which is able to measure conductivity in a substance. By doing this, I discovered that sugar is not conductive. This means that it is not a good medium for electricity to use as a path to charge something. Measuring the sugar's conductivity did not alter its chemical ID, so it is a physical property.
4. MALLEABILITY
Measuring the malleability was a very simple process. I tried bending or stretching out the grains of sugar by hammering them and applying pressure to them, but in every case they just broke down into smaller grains or turned into a fine powder. I can conclude that sugar is brittle and not malleable because it is not able to bend in order to change its shape. Even though I broke down the sugar into smaller pieces by doing this, the pure substance of the sugar still remained the same - making it a physical property.
5. TASTE
'Sweet' is the only word I can think of to describe the taste of sugar. It doesn't have a distinct taste except for sweetness. The taste of the sugar in its solid form is a physical property because tasting it did not change its chemical ID.
CHEMICAL PROPERTIES- Reactions that a substance can have that alter its chemical ID.
1. ADDING HEAT
When I heated a small pile of sugar with a blow torch, the sugar began to burn and melt into a dark brown carmel-liquid substance. When it cooled, it turned almost black and was hardened. This is a chemical change because it can not be reversed and the chemical makeup of the sugar was altered.
2. FLAMMABILITY
While I was heating the sugar to discover it could turn into a liquid, I also discovered that it is slightly flammable. Once the sugar began to liquify, it caught on fire for a brief amount of time. This means that sugar reacts with oxygen (in the fire) by catching on fire. The chemical ID was changed by burning the substance - making it a chemical change.
3. VINEGAR REACTIVITY
I poured some sugar into a cup with vinegar to find out if a chemical reaction would occur. To my disappointment, nothing really happened except for the sugar slowly dissolving into the solution of vinegar. No fizzing or bubbling occurred that would indicate a chemical change had occurred. Sugar is not reactive with vinegar.
4. REACTION WITH SULFURIC ACID
I could not test this one at home, but I did discover by doing some research that sugar reacts with sulfuric acid. When mixed with the sulfuric acid, the water is removed from the sugar - so only carbon is left. This process essentially dehydrates the sugar. The color also changes to a light yellow and then brown color. The composition procedes to bubble and fizz. Finally, the substance expands starts to create and emit smoke. This is a chemical reaction because the chemical ID of the sugar would be altered.
(http://chemistry.about.com/b/2011/07/23/sulfuric-acid-and-sugar-reaction.htm) . A video of the reaction can be observed here: http://www.youtube.com/watch?v=_gG0UAX3V7c
5. REACTION WITH HYDROCHLORIC ACID
To my surprise, my dad happened to have a bottle of hydrochloric acid in the garage to clean electrical connections in his car. When I poured hydrochloric acid over a small pile of sugar, nothing happened. The sugar just floated to the bottom of the cup. I can now conclude that sugar does not react with hydrochloric acid.
WORKS CITED:
Helmenstine, Anne. "Sulfuric Acid and Sugar Reaction." Chemistry - Periodic Table, Chemistry Projects, and Chemistry Homework Help. 23 July 2011. Web. 19 Sept. 2011. <http://chemistry.about.com/b/2011/07/23/sulfuric-acid-and-sugar-reaction.htm>.
"Sulfuric Acid in Sugar - YouTube." YouTube - Broadcast Yourself. Web. 19 Sept. 2011. <http://www.youtube.com/watch?v=_gG0UAX3V7c>.
Good posting Erika! Your posting was not too long and explained why your observations were physical or chemical. Although it was not too long, you might want to expand on your information some. I enjoyed your pictures and the video of the reaction with acid. I think you can embed the actual video in your blog which would be nice. I thought your posting was very informational! Good job!
ReplyDeleteNicole Holzer
Your blog has a really nice look! However, your organization could use a little more work. Instead of just labeling your reactions, why not trying to use paragraph form? This is sometimes seen as a better way to write up reports. However, this is a blog. Good content and material and great use of pictures!
ReplyDelete