Laboratory Techniques and Measurements Essay
The lab performed was laboratory techniques and measurements. The purpose of this lab was to familiarize ourselves with different techniques used in the lab, taking proper measurements, and how to use the International System of Units (SI). Throughout lab we learned about mas, volume, length and temperature, and to be able determine density and concentration. To be able to documents properly and make effective observations we must be able to understand the International Measurement System. Length, temperature, time, and volume are measured by this system.
There are many different techniques to measure all of the metric system. Length is measured by meters. This is the measurement of distance between an object from end to end. Temperature in the metric system is measured by Kelvin. Volume is the amount of space that a three dimensional object takes up. This is measured by cubic meter.
A graduated cylinder is often used to measure the volume. Throughout out the lab we took all these different measurements, and also expanded the experiments to learning about density and concentration by using the same measurement techniques.
Density is used to describe how heavy an object is. In the lab we performed several experiments. The recorded experiment was the volume and density experiment. For this experiment I hypothesized that the water is denser than alcohol. For this experiment we used water, isopryl alcohol, a scale, a graduated cylinder, and a pipet. In the experiment we took the mass of the graduated cylinder the water and alcohol would be measured in. The mass of the water was measured, and we calculated the density with the data we obtained. Then we repeated the steps, but with alcohol. Below is the chart of the results: Data Table 4: Liquid measurements.
Mass B – A
with liquid (g)
In the graduated cylinder the volume of the water was 5mL, the mass of the graduated cylinder was 16.4 g, and the mass of the cylinder with the water was 21 g. With this information we were able to calculate the density of the water, which was .92 g/mL. The measurements of the alcohol required the same procedure. The volume of alcohol in the graduated cylinder was 5 mL, the graduated cylinder without the alcohol remained the same at 16.4 g, and with the alcohol in the beaker the mass was 20 g. The information gathered
concluded that the density of the alcohol was .72 g/mL. The percentage error for the water was -8% and for the alcohol it was -8.39%. The water density is 1 g/mL and the density for alcohol is .786 g/mL. The calculations are slightly different, but they fall within the proximity. I hypothesized the water would be denser and as proved by my experiment I was correct. To reduce errors in the future the measurements of the water and alcohol should be exact on the graduated cylinder.