Sucrose Lab Report

Introduction

This lab was conducted at Station 8 in Room 103 of the Chemical Sciences and Engineering Building at Michigan Technological University. The primary objective of this lab was to: Find the viscosity in cP of 10 wt% sucrose, 20 wt% sucrose, 30 wt% sucrose, 40 wt% sucrose, 45 wt% sucrose, 50 wt% sucrose, 60 wt% sucrose, 65 wt% sucrose, and 2 mystery sucrose and water solutions at room temperature, 40°C, and 60°C.

The secondary objectives of the lab were to: Find the dependence of viscosity in cP on the concentration in wt% sucrose and temperature in °C. Create functions for the relationships. Determine the concentrations of the two mystery solutions in wt% sucrose by using the functions found that relate viscosity in cP to concentration

Experimental Viscosities in cP of 65 wt% Sucrose and 30 wt% Sucrose Solutions at Tested Temperatures in ˚C Compared to Literature Values of Viscosity in cP with Percent Error

Concentration of Sucrose (% weight) Temperature of Solution (˚C) Average Viscosity of Sucrose Solutions Calculated (cP) Literature Value of Viscosity of Sucrose Solutions (cP) % error

65 20.7 138.67 147.2 5.79

65 40 42.88 44.36 3.34

65 60 18.31 17.9 2.29

30 20.7 2.9376 3.187 7.83

30 40 1.999 1.833 9.06

30 60 1.239 1.2 3.25

The graph of the viscosities at the tested temperatures for the 30 wt% sucrose solution can be seen in Figure 1. The graph of the viscosities at the tested temperatures for the 65 wt% sucrose solution can be seen in Figure 2. In both graphs error bars are included, but due to scale an the small amount of error, they cannot be seen.

The viscosities collected by the class at each temperature versus concentration are graphed in Figure 3. The complete set of data from the class can be found in Appendix B. Figure 4 shows the inverse viscosity graphed to obtain a linear function to describe the data.

The equation for the data at 20.7 ˚C can be found in Equation 3.

This value makes sense since all of the values for viscosity of Mystery 1 are between those collected for the 10 wt% sucrose and 20 wt% sucrose solutions. It’s average density of 1.037 g/mL is near that of the 10 wt% sucrose solution’s of 1.038 g/mL, showing it is closer to 10 wt% sucrose than 20 wt% sucrose.

The concentration of Mystery 2, calculated using average viscosities collected at each temperature, and then an overall average of the concentrations calculated from Equations 3-5, was found to be 28.725 wt% sucrose. This value makes sense since most of the values for viscosity of Mystery 2 are between those collected for the 20 wt% sucrose and 30 wt% sucrose solutions. It’s average density of 1.0975 g/mL is between that of the 20 wt% sucrose solution’s of 1.079 g/mL and that of the 30 wt% sucrose solution’s of 1.129 g/mL.