Soil Moisture

For this test, we used a piece of aluminum foil, about a square foot in size, to make a small tray by rolling and flattening the sides and folding over the corners. We then weighed this tray and found that it was 2.9 grams. We added several spoonfuls of soil to the tray and weighed it again, finding it to be 86.9 grams. This means that the weight of the soil alone was 84.0 grams initially.

The soil was then placed into a drying oven overnight at 90-95 degrees and retrieved in the morning. The pictures below show the difference in the appearance of the soil. 

Before drying oven:

After drying oven:

The weight of the tray of soil after coming out of the drying oven was 85.2 grams. This means that there was 1.7 grams of water in the soil.

Calculations:

The percent of water by mass for the soil was 2.0% as calculated below.

       This is a relatively low percentage of water content in the soil compared to other groups in the class, who had as much as 12% to 13% water. 

       These values accurately represent our soil because of its composition, which was 40% sand, 50% silt, and 10% clay. The other groups that had higher water percentages had much more clay in their soil and much less sand. Sand doesn't hold water very well and allows it to go right through it, and clay holds water very well.