Due Date: Monday, January 7, 2013 Independent Variable: The material of the seed crystal. (Wood, Plastic,Metal) Dependent Variable: The amount of crystals grown

Test question – Do different materials for the crystal seed affect the sugar crystal’s growth? Hypothesis – If the seed material is plastic, then the sugar crystals will show more growth. Reason for hypothesis – The plastic is smoother than the rest of the materials, and so the crystals may be able to grow more on the plastic.

 To Start this project, I began by boiling two cups of city water with five cups of granulated sugar In a pan on top of the stove. Once the sugar was fully dissolved I filled three jars with the boiled sugar. The jars contained rectangular seed crystals that were made of metal, plastic, and wood. This project was started on November 26 th, 2012 at 6:30 p.m.  My Independent test variable is material of the seeds. (Wood, Plastic, Metal)  My Dependent test variable is the amount of crystals grown.  The factors I controlled in the experiment are – I had the same size jars, they were kept in the same place,(same temp.) I put the same amount of sugar in each jar, and had the same size seeds.

No crystals have grown yet. The solution line is about 3 ¾ in. No crystals have grown yet. The solution line is about 3 ½ in.

Wood-Crystals have grown on the bottom of the jar. There is only a few that are actually on the seed. There is no change in the solution line Plastic-Small crystals are on the seed. And a couple of crystals have started growing on the bottom. There is no change in the solution line Metal- Crystals are starting to grow on the crystal seed and on the bottom of the jar. There isn’t any change in the solution line.

Plastic- The crystals are growing larger. More are growing on the side of seed. The solution line has gone down about 1/8 of a cm. Wood- There isn’t much change in the amount of crystals grown so far. and not much change in the solution line either. Metal- The crystals are growing bigger. A few have started growing on the back of the seed. There is also a few more crystals on the bottom.

Metal- Crystals have almost completely covered the seed on the front side. There is also a lot growing on the bottom. The solution line is lower. Plastic- Two big crystals have grown on the side of the seed. More have grown on the bottom. The solution line is lower. Wood- Crystals are growing on the side of the crystal seed. There is a few growing on the side of the jar.

Wood- The crystals on the side of the seed have grown bigger. More have grown on the glass. And a few crystals have broken off and are floating on the top. Plastic- Bigger crystals are growing on the back of the seed. Some have also started growing on the glass. Metal- There are a lot of crystals on the bottom and on the seed. There are big crystals on the side of the seed.

Plastic- There is a clump of crystals growing on the side of the seed. The solution line has gotten lower. Metal- The seed is almost completely covered on both sides with crystals. The crystals on the bottom are growing bigger. Wood- The crystals from the bottom of the jar have grown up and attached to the crystals on the seed.

Wood- Little crystals have grown on the front of the seed. More are floating on the top. Plastic- Another big crystal has grown on the seed. There are more little crystals on the back. Metal- Medium sized crystals are floating on the top. The bottom of the jar is covered with big crystals.

Wood- There hasn’t been very much change. It looks like only a couple small crystals have grown on the back. Plastic- The bottom looks like the crystals have grown a little bit bigger. Metal- The crystals that are on the seed are growing wider and longer. There is also more on the side of the jar. Just little crystals though.

Plastic- The sides of the jar has bigger crystals. A couple more crystals are floating. Wood- Crystals are growing larger on the side and the bottom. Metal- There are crystals all around the sides of the seed now.

Plastic- The crystals in the front and the back have grown bigger and are longer. Wood- The back of the seed has grown some tiny crystals. Metal- A few crystals have grown closer near the top of the solution line. The crystals are growing from the bottom of the jar and up the side.

Metal- The crystals on he seed are growing larger. They stick out from the seed now. Wood- There are some bigger crystals growing on the seed and the bottom of the jar. Plastic- The sides of the seed is almost covered with crystals.

Metal- Not much change has occurred. Just a few little crystals on the side of the jar. Wood- More crystals have grown on the glass. Plastic- More crystals have grown near the bottom of the jar. There is now a clump of crystals there.

Metal- The crystals from the bottom are growing more up the sides of the jar. Wood- The little crystals have grown a little bit bigger. Plastic- The crystals have grown more on the right side of the seed.

Hypothesis- If the seed material is plastic, then the sugar crystals will show more growth. My data did not support my hypothesis. Plastic Seed- Grew about 56 crystals on the Seed. The biggest crystal was ¾ cm. long and about ½ cm wide. Wood Seed- Grew about 48 crystals on the seed. The biggest crystal was ½ cm. long and ½ cm. wide. Metal Seed- Grew about 88 crystals on the seed. The biggest crystal was 1 ¼ cm. long and 1 cm. wide. My data show that the metal seed had the most growth on the seed than the plastic and the wooden seeds.

The objectives of this project was to learn the differences between chemical and physical changes in matter, To understand that physical conditions can affect crystallizations, to learn the differences between a mixture and a pure substance. Doing this project, I learned that different physical conditions can make changes in crystallizations. When I put different materials as the seeds, I saw that there is differences in growth of the crystals. Some factors that could have affected the crystals growth are different textures of the seed. (The scratchiness of the wood, smoothness of the plastic) Another factor could have been the size of the crystal seed. Some uncertainties I had were that I might not have given each jar the same exact amount of solution. The seeds weren't exactly the same the same size either. If I did this project again, I would try doing different amounts of solution in each jar. I would also like to try adding more sugar to one jar.