Density Lab Report

Density is defined by its heap per unit pile, and is most often written in mathematical ground as d = m / vMass is usually given in grams, g, and stack is given in cubic centimeters, g/cm3, or, grams per milliliter, g/mL. Density is non a property that depends upon the amount of substance present. For example, unitary gram of bear and one ton of lead have the same tightness. Density similarly does depend on temperature. For instance cold wet is denser than warm weewee ice is less dense than both. The method personad for determining the dumbness of a substance depends on the nature of the substance. In this lab the densities of unfathomable irregularly shaped solids and liquids was rigid.Accuracy and precision of the results get out be estimated, and attention will be paid to the correct use of the significant figures. The experiment flack that will be used will tell the can and vividness of the alloy and liquid determined by measuring these two quantities with a gr aduated cylinder and biuret. Procedurea) The density of surfacesFirst I obtained a criterion of unknown metal. Recording the unknown number. I used only one type of metal for this part of the experiment.The unknown metal that I was instructed to use was a chunk, therefore, I used a 50ml graduated cylinder. When using the 50ml cylinder, I filled it with peeing to round the 35ml mark. so record the exact volume of water that was added. I placed the cylinder and water on the relief and save the mass to every 0.1g. I added the metal to the graduated cylinder until the water level increased by approximately 2.0ml. Being received to tap the sides of the cylinder to release any air bubbles. I wherefore recorded the volume of the water plus metal to the nearest 0.1mL.Then recorded the total mass of the cylinder, water and metal. I added more pieces of metal to the cylinder until the water level had increased by 2.5ml. Then I recorded the exact volume of water plus metal and total mass of cylinder, water and metal. I repeated the procedure twice more. Being cautious not to go over the 50ml mark. And recording the data each time.CalculationsI determined the total volume of metal in the cylinder by subtracting the volume of water from the volume of water plus metal. Then ensnare the corresponding mass of metal by subtracting the mass of the cylinder and water from the mass of the cylinder, water and metal. I plotted out the graph display the total mass of metal on the y-axis, and the volume on the x-axis. I found the slope of the line by taking two ergodic points from the graph, performing the slope formula and finding the density. From the table provided, I identify the unknown metal to be smooth-spoken.b). Determining the density of a water/ethanol mixture.I obtained an unknown solution from the instructor. Then recorded the number of the solution.Then I rinsed a burette with a little of the ethanol solution, and filled the buret with that same solution . I read the buret level to the nearest 0.05ml. Then weighed an empty 250ml Erlenmeyer flask. I turned the knob of the buret and put approximately 23.4ml of solution into the flask. I read the buret again, to 0.05ml and recorded.Next I weighed the flask and its contents, by placing the flask on the balance and recording the temperature of the solution. I then determined the density of the solution by taking the mass of solution and dividing it by the volume of solution. Repeating the procedure twice more using a clean flask and the same balance each time.CalculationsFor each of the triad trials I calculated the density of the solution and determined the mean, average divergency from the mean, percent precision and the range. I then drew a calibration curve from the data given on page 17 of my science lab Manual.DiscussionBased on the value of my density, and based on the literature determine given on page 16 of my Laboratory Manual, the unknown metal is silver. The density I ha d obtained from the slope of the graph was 9.09g/mL. I then compared my density to the chart given, looking for a similar density. The density of my unknown metal was not exact with a particular metal given inthe chart, but I kept in mind that the density of silver can vary depending of the state it is in.Error AnalysisThe possible sources of error in finding the density of the unknown metal and liquid would have to be my consistency throughout the experiment. I had approximated with my bare eye and was not consistently exact. Therefore, there was an inaccuracy in reading the volume displaced from the graduated cylinder and the biuret.