Friday, September 10, 2010

The Chemical and Physical Properties of Bread

I chose to use bread for my project because I thought since it was made of flour, it would react to a lot of different things.

5 pieces of bread
Freezer/Ice Cubes
Liquid-Plumber gel

Clorox bleach
Suave Hair Spray
4 Glass Cups
3 Pieces of Bread
Sally Hansen Nail Polish Remover

Physical Properties: 
Property of a compound that can change without involving a change in chemical composition; examples are the melting point and boiling point

1) My first physical property was the ability of the bread to be cut. Because the bread is soft, it is easily split into many pieces.

2) My second tested physical property was freezing. I put the bread into a bowl of ice in the freezer and let it sit for about 25 minutes. I tested for progress along the way and the bread had turned solid relatively quickly. When I pulled it out, it was not bendable, and could've been broken in half like a cracker. This did not change the state of the bread which still made it a physical property.

3) My third physical property was hammering the bread. It was easily crushed because of the soft material that the bread is made with. After hammering the whole piece just once, the entire piece of bread was as flat as a piece of paper.

4) My fourth physical property was soaking the piece of bread in a bowl of water. I did this for about 20 minutes, and by the end when I took it out, the bread was soggy and had absorbed the water. It had absorbed so much water that the bread was falling into pieces. 

5) My fifth and final physical property was boiling the water on the kitchen stove. I left the bread in for about 20 minutes, and by the end the bread had puffed up and was full of water. There was a temperature change but only because the water inside of the bread was hot. 


Chemical Properties: A
 property used to characterize materials in reactions that change their identity.

1) My first chemical experiment was using nail polish remover to soak the bread in. At first there was a reaction, and the bread started bubbling, but from then on the bread just soaked in the nail polish remover. The pink color was absorbed into the bread, and there was a scent from the original liquid, but other than that there were no serious reactions to the remover.

2) The second test I did was soaking the bread in Clorox bleach. There wasn't an immediate reaction but after about 10 minutes there was a foaming on the top of the cup and the bread was still there, but soggy. After about 20 minutes there was a yellowish tint to the bread that wasn't initially there, and after 30 minutes, the bread had completely dissolved and there were no remains left. This was an apparent chemical reaction because of color change, dissolving, and foaming.

3) The third chemical test I did was lighting the bread on fire. It was not easy, and at the beginning the bread wouldn't catch fire. After about 20 minutes of trying, the top layer of the bread had burned and been crusted over with a black layer. There was an obvious odor coming from the burning, and the color change that you look for in a chemical change. 

4) Another test I did was used liquid plumbing gel mixed with the bread. After about 10 minutes there was a strong odor, and brown coloring showing on the bread. The bread had also started to inflate, and the color continued to change. There were also small holes in the bread from what seemed to be the beginning of it dissolving. After about 30 minutes, there were little remains of the bread, and the color had changed to a more tan like solution.

5) The last chemical property that I tried on the bread was hair spray. I thought this would be a good idea because there might be a bubbling from a reaction on the surface. After coating the bread in a few layers of hairspray, I waited for about 40 minutes and there was no change at all. When I picked up the bread, it was hard but not crunchy, and there were no signs of color change or any type of dissolving or bubbling. 

Overall, the experiment was successful. I found that bread only reacts to a limited amount of products, even though it is made of such a reactant material. The physical properties outnumber those of the chemical properties because bread is such an easily manipulated item.