Question

Hello, could u please help me to find in retention time, the name of the unknowns, the grahp question #3 and #4. Thanks!

Gas Chromatography CHM 112 Report Sheet 1. Complete the information in the data table. 2. Identify the unknowns Data Table Name Methanol Ethanol 1-Propanol 1-Butanol Formula CH3OH C2H50 C3H80 C4H100 Formula Weight 32.04 J/mol 46.07 J/mol 60.09 J/mol 70.12 J/mol Boiling Point 64.7C 78.37C97C 117.7C Retention Time 1.80 5.76 In Retention Time 14.20 Unknowns Name Retention Time 2.20 4.30 3. Graph "In (retention times) vs. number of carbon atoms” in the known samples using Excel. . • • . . . Give the graph a title Label the x and y axis Draw a line of best fit . Equation .R 4. Use the graph to predict the retention time for 1-pentanol.

Answer 1

Number of carbons Rt In(Rt) Methanol 1.80 0.5878 Ethanol 2 2.19 0.7839 1-propanol 4.20 1.4351 1-butanol 5.76 1.7509 Unknown-1: as the Rt for this unknown is 2.20 which is close to the Rt of ethanol. Unknown-2: as the Rt for this unknown is 4.30 which is close to the Rt of 1-propanol. 3) From the graph, Equation of a line of best fit: y = 0.414x + 0.104 and R2 = 0.961 4) 1-pentanol contains 5 carbons, so put x = 5 in the equation: y = (0.414*5) + 0.104 = 2.17 this is In(Rt) = 2.17 Rt = e12.17 = 8.76 (time units)

Ε А 1 Rt 2 Methanol 3 Ethanol 4 1-propanol 5 1-butanol в с I n(Rt) Number of carbons 1.8 0.5878 2.19 0.7839 4.2 1.4351 5.76 1.7509 In(Rt) vs No. of carbons In(Rt) y=0.414x + 0.104 R2 = 0.961 + ? No. of carbons 3 H