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11/29/23, 10 : 50 AM Chem21Labs - online lab submission. Page 3 of 7 https://www2.chem21labs.com/student2/ ? mode=assign&assignment=113 repeat until the desired lines are removed To see the x and y values at the intersection of two lines, place your mouse at the intersection and read it's position in the upper left corner of the graph. Part C: Pressure vs. Temperature Measurements Pressure vs Temperature Plot will not appear until atmospheric pressure is entered! 1/y vs. x ln(y) vs. x Draw Lines Mouse Coordinates: Enlarge Graph Upload the pressure-volume plots (2) and the pressure-temperature plot (1) below. Files must be jpeg, png or gif format--not pdf! Instructor Assigned Grade Based On Plot of V syringe vs. 1/P air More Information NG 20

11/29/23, 10 : 50 AM Chem21Labs - online lab submission. Page 6 of 7 https://www2.chem21labs.com/student2/ ? mode=assign&assignment=113 Because P.V=nRT -> P=nRT.(1/V) and in the equation of y=mx+b, the slope would be m. Therefore in the equation of P=nRT.(1/V), where P is the y-axis and (1/V) is the x-axis, the slope of the equation equals nRT or slope = n.R.T Edit Answer 4. Using your answer to the preceding question and your slope from the V syringe vs. 1/P air plot (mL-torr), and assuming that the temperature of the laboratory is 298 K, how many grams of air (average molecular weight 28.8 g/mol) were in your sample of air? Be careful with units! You must click the 1/y vs x button for the graphs above before submitting your answer. Try 1: ✘ 0.00346 Try 2: ✘ 3.0457E-3 Try 3: ✔ 4.0075E-3 2 4 Info (100) 5. Why must you be careful not to grasp the barrel of the syringe when making pressure measurements? NG 5 Since pressure is dependent on temperature, any measurement of the relationship between pressure and volume requires that temperature remain constant. Grasping the syringe barrel with your hand will heat up the gas inside the apparatus, increasing the pressure. Since pressure and volume are inversely proportional, grasping the barrel increases pressure, the volume would be exerted, and that would result in a decrease in the volume of the syringe, making the volume lower than expected. Edit Answer 6. How is the value of κ which you calculated related to T , the temperature in Kelvins? Using your value of κ , write the formula for conversion of the Celsius temperature t to the Kelvin temperature T . NG 6 The value of k equals the y-intercept divided by the slope, or in the equation of y=mx+b, k equals b divided by m. Therefore, the k value in my plot was 332.69 Celcius degree. Since the relation between the two scales of t ( o C) and T(K) is T(K) = t( o C) + k, my formula for the conversion of the Celcius temperature to the Kelvin temperature would be T(K) = t( o C) + 332.69 Edit Answer 7. Your formula may differ from the usually accepted formula T = t (°C) + 273.15. The error is most probably not your fault, but instead is due to the way in which the experiment was done and the value of κ calculated. Why might your experimental value differ from the accepted value? NG 4 The usually accepted formula T(K)=t(C) + 273.15 resulted from the experiment under standard pressure and temperature conditions, which is 1atm (or 760 torr) and 0 o C or 273K. However, in our experiment, the experiment was conducted under the pressure of 763.7 torr or 1.005 atm, which is not the standard pressure condition. Since the experiment was done and the data collected were not under standard conditions, the value of k calculated will also be different from the standard one, which is 273.15. Edit Answer 8. Use the Ideal Gas Equation to express the slope of your plot of P air vs . t algebraically in terms of n , R , and V . NG 6 PV=nRT -> P = T.(nR/V). In the equation y=mx+b, the slope would be m. Therefore, in the equation of P=T.(nR/V), where the P value will be the y-axis and the T value will be the x-axis, the slope equals nR/V, and nR/V = 2.5586. Edit Answer