Tuesday 8.31.10

Today in class we took a few minutes to label all the important things in the room like the fire exits and water showers. Then we identified some materials. We identified a beaker, flask, Bunsen burner, a ring stand and a funnel.  We also talked about different types of measurements. To start off we got a ruler with a filled in a line on top. We had to estimate the length to the closest we can. With that you only have one guess. That means when you find your measurement it is not exact so you estimate to a reasonable length. When trying to find the measurement of a graduated cylinder, you measure from the lower dip in the water. Then we split into lab groups and started working on measurements. We took measurements in different ways. We found the smallest reading device for each utensil. The most accurate was a 10 ml graduated cylinder. It has the smallest reading device so it is most accurate. Some reading devices were 25 ml for a 400 ml beaker, 10 ml for 100ml beaker. 1 ml for 100 graduated cylinder and .2 ml for 10 ml graduated cylinder, which is the most accurate. After that we take a buret clamp and place a 250 ml beaker under it so it will catch the liquid. Fill the buret with water then open the valve and see how much water drains. The unique this about a buret is that the measurement starts at 100 then drops to 0. The reason for this is so you can see how much water or liquid you dropped or took out. We then recorded how much water was emptied out to the nearest 10nth. Then you let the water drain for 3 seconds and you record how much water drained. That is when we started cleaning up. This lab will be continued…