The Density of Glass for A Graphical Determination

Question: Disucss about The Density of Glass for A Graphical Determination? Answer: Purpose The main purpose of this experiment is to create a graph which will be used for the determination of the density of the glass i.e. in this case glass marbles. Introduction (A) Density (D) - Density is a physical property of a substance which is generally used to identify that substance. Density (D) may be explained as the ratio of the mass (m) of a substance to the volume (v) occupied by that mass. Density is an intensive property of a matter thus it can be said that the value of density of a matter is independent of the quantity of the matter present. It generally shows how tightly matter is crammed together. The formula for density is given as follows: D= Mass/ Volume or D= m/v The density may be expressed as: g/cm3 or g/mL (1cm3 = 1mL) (B) Indirect Measurement- Indirect Measurement may be defined as a measuring approach to measure things using alternative measurements and properties. Indirect measurement generally involves properties such as Pythagoras theorem, proportions, similar triangles or polygons and others. (C) % Deviation- Percentage deviation may be defined as the measure of how much the mean of a set data differs from the known theoretical value. The formula for the Percentage (%) deviation may be given as follows: Percentage Error = [(Observed value True Value) / True Value] 100 % (D) Dependent variable Dependent Variable may be defined as the variable which is measured in an experiment. The dependent variable generally depends upon the independent variables. For example in this experiment density of glass is the dependent variable. (E) Independent Variable An independent variable may be defined as the variable that can be changed during an experiment. It does not change due to the changes in the other variable. In this example the Mass of water and mass of glass are the examples of independent variable. These variables are generally used to establish some relationship to determine what effect is caused in the dependent variables due to the changes made in the independent variable. (F) Slope of a Line The slope of a line may be defined as the ratio of the amount of by which values on the Y-axis of a graph increases when certain amount is increased in the values in X-axis. Slope of the line how steep is the line, i.e. how much y increases as x increases. The value of the slope is constant everywhere in the line. The slope of a line may be expressed as: Slope = (change in y)/ (change in x) or m = y / x (G) Straight Line Equation Form- It may be described as straight line on the coordinate plane which can be described by the following equation: y = mx + b Where, x, y = Coordinates of any point on the line m= slope of the line b = It is the intercept (where the line crosses the y- axis) The straight line equation form is generally used for two main purposes which are: as a compact way of defining a particular line and to locate all the points on a line. (H) Primary Date - Primary data may be defined as the data which is either observed or collected from the first-hand experience during an experiment or observation. (I) Secondary data Secondary data may be defined as the information that is obtained after interpreting or evaluating the primary data. Diagram Procedure Following is the procedure for conducting the experiment: 1) Put on your safety goggles and Lab apron: 2) Take 100 mL graduated cylinder and fill with about 40mL of tap water. Record this on your primary data table. 3) Make Sure that the above volume is out to the correct precision. 4) Find the combined mass of the graduate cylinder and tap water. Record this on your primary data table. 5) Using your container of glass marbles, take out one marble and place it into the water in the graduate cylinder. Record both the new volume and the new mass into your primary data table. 6) Continue the above process for all the fifteen marbles that are in your container. 7) When completed, pour out the excess water into the drain and place the wet marbles on a paper towel for drying and returning to its container. Primary Data Table Trial Mass of water GC Glass(g) Volume of water Glass marbles (mL) 0 ( Zero Marble) 179.44 g 40.0 mL 1 183.76 g 41.0 mL 2 188.13 g 42.0 mL 3 192.27 g 44.0 mL 4 196.61 g 46.0 mL 5 202.30 g 48.0 mL 6 206.75 g 50.0 mL 7 210 .22 g 52.0 mL 8 214.32 g 54.0 mL 9 218.07 g 56.0 mL 10 222.33 g 58.0 mL 11 226.51 g 60.0 mL 12 230.89 g 61.0 mL 13 235.09 g 62.0 mL 14 239.07 g 63.0 mL 15 243.35 g 64.0 mL Processing the data (Secondary data) 1) For the trial #1 as a sample calculation, determine the mass of the glass in the graduate cylinder. From the Primary data table we can obtain the following data, i) The Mass of water+ Mass of Graduated cylinder+ Mass of Glass marble for Trail #1 = 183.76g-------- (a) ii) The Mass of Water + Mass of Graduated cylinder from Trial #0 = 179.44 g ------- (b) Thus, the in order to obtain the mass of the glass marble for the Trial #1 , subtract (b) from (a). Hence, (183.76 179.44) g = 4.32 g The mass of the glass marble for the Trial #1 is 4.32 g. 2) Place the above mass of glass for trail #1 in the secondary data table. 3) There is now no need to show the method again, but simply place the total glass mass that was in the graduate cylinder for the rest of the 15 trials in the secondary data table. 4) For the trail# 1 as a sample calculation, determine the volume of the glass marble in the graduate cylinder. From the Primary data table we can obtain the following data, i) (Volume of the water + Volume of marble) for Trial #1 = 41.0 mL --------- (a) ii) Volume of water for the trial #0 = 40.0 mL -------- (b) Thus the volume of glass marble in the graduate cylinder = (a) (b) = 1.0 mL. 5) Place the above volume of glass for trial #1 in the secondary data table. 6) Determine the volume of the total glass in the graduate cylinder for each of the remaining trials and place the data in the secondary data table. 7) For trial #1 as a sample calculation, determine the density of the glass marble in the graduate cylinder for each of the remaining trials and place that data in the secondary data table. We know that the Density(D) = Mass/ volume For the trial #1, Mass (m) = 4.32 g Volume of the Glass marble (v) = 1.0 mL Thus, D = m/v = 4.32/ 1.0 = 4.32 g/mL Thus the density of the glass marble for the trial #1 is 4.32 g/mL. 8) Determine the density of the total glass in the graduate cylinder for each of the remaining trials and place that data in the secondary data table. 9) Using your secondary data table and the graphing handout sheet, construct a graph of Mass of glass versus volume of glass versus volume of the glass. Secondary data table Trial # Mass of Glass (g) Volume of Glass (mL) Density of Glass (g/mL) 1 4.32 g 1.0 mL 4.3 (g/mL) 2 8.69 g 2.0 mL 4.3 (g/mL) 3 12.83 g 4.0 mL 3.2 (g/mL) 4 17.17 g 6.0 mL 2.9 (g/mL) 5 22.86 g 8.0 mL 2.9 (g/mL) 6 27.31 g 10.0 mL 2.73 (g/mL) 7 30.78 g 11.0 mL 2.79 (g/mL) 8 34.88 g 13.0 ml 2.68 (g/mL) 9 38.63 g 15.0 mL 2.58 (g/mL) 10 42.89 g 16.0 mL 2.68 (g/mL) 11 47.07 g 18.0 mL 2.62 (g/mL) 12 51.45 g 20.0 mL 2.57 (g/mL) 13 55.65 g 21.0 mL 2.65 (g/mL) 14 59.63 g 23.0 mL 2.59 (g/mL) 15 63.91 g 24.0 ml 2.66 (g/mL) Graph Conclusions and Questions 1) The main purpose of this experiment is to determine the density of the class marble from the Graph of mass vs volume. 2) The range of Density may be calculated from the Difference between the maximum value of density and the minimum value of density. Thus Range of Density = Dmax DMin = (4.3 2.57) g/mL = 1.73 mL 3) The percentage deviation is determined in the following manner, of all the density = 44.15 g/mL Arithmetic mean = 44.15/15 = 2.94 Percent Deviation = [(4.3 -2.94)/2.94] 100 = 46.25% 4) The easiest instrument that was used during the experiment was scale. It was easier to use because there was very little chances of the error in reading in scale and it is easier to take reading from a scale. 5) a) Weight = 0.250 pounds = 113.398gm Density obtained from the graph = 2. 94 g/mL Volume = 113.398/2.94 = 38.57 mL b) Dimensions of glass window are as follows: Length = 32 inch = 81.28 cm Breadth = 22 inch = 55.88 cm Width = 0.125 inch = 0.3175 cm Volume = L B W = (81.28 55.88 0.3175)cm = 1442.06 cm3 1000 cm3 = 1 L Thus, 1442.06 cm3 = 1.442 L = 1442 mL Mass = 1442 2.94 = 4239.48 g