# Viscosity

Topics: Measurement, Accuracy and precision, Reaction time Pages: 8 (2122 words) Published: June 22, 2013
Viscosity Investigation
Research Question: How does the concentration of C6H12O6 affect the viscosity of a C6H12O6 solution?

Hypothesis
I believe that as the C6H12O6 concentration increases, so will the viscosity of the solution. I think so because the increased number of electrons caused by the greater mass of C6H12O6 will lead to stronger Van-der-Waals forces. Furthermore I believe that because of the increase of C6H12O6 particles, indicated by the increased number of moles of C6H12O6, there will be stronger dipole-dipole forces and hydrogen bonds. Thus I believe that concentration affects viscosity in such a way as that the stronger the concentration of the solution, the stronger the viscosity of the solution. Variables

Independent variable:
* Concentration of C6H12O6
Dependent variable
* Time it takes to pour 1cm3 of the C6H12O6 solution as an indirect measurement of the viscosity of the solution Controlled variable
Temperature of the solution| Controlled by putting all solutions in a water bath set at 35°C until they have reached temperature of 35°C| Distance solution travels| Controlled by always pouring out 1cm3 of all the different C6H12O6 solutions for one reading| Pressure inside the burette| Controlled by always using the same burette| Procedure

Apparatus

*
* H2O
* C6H12O6
* 1 25cm3 measuring cylinder (uncertainty: ±0.5cm3)
* 1 50cm3 burette(uncertainty: ±0.1cm3)
* 5 25cm3 flasks + fitting bungs
* 1 electric scale(±0.0005g)
* 1 thermometer(±0.005°C)
* 1 stopwatch(±0.005s)
* 1 water bath at 35°C (±5°C)

Method

In this experiment the concentration of the Glucose solution is being varied in order to evaluate its effect on the viscosity. These solutions with different concentrations will be made by dissolving varying amounts of provided C6H12O6 in H2O. The solutions and their concentrations are as follows: Concentration of C6H12O6[mole dm3]| Mass of C6H12O6 powder [g]| Volume of H2O [dm3]| 01.4| 5| 0.020|

01.1| 4| 0.020|
0.83| 3| 0.020|
0.56| 2| 0.020|
0.28| 1| 0.020|

In order to decrease the uncertainties as much as possible, use 1. Prepare the solutions:
2.1. Measure 0.020 dm3 of H2O in a 0.025 dm3 measuring cylinder 2.2.1. Make sure to measure from the bottom of the meniscus at eyelevel in order for the measurement to be as exact as possible. 2.2. Weigh 5g of C6H12O6 powder

2.3.2. Use an electric scale which is precise to three decimal places in order to get an accurate reading 2.3.3. Ensure that both weighing scale and the scale are completely free from any dust or other particles in order to prevent imprecision in the weighing 2.3. Pour water and C6H12O6 powder into an 0.025 dm3 flask which has previously been labeled with the correct concentration of C6H12O6 being made (1.4 mole/dm3; 1.1 mole/dm3; .83 mole/dm3; .56 mole/dm3 or .28 mole/dm3) 2.4. Close flask with a fitting bung and shake well in order to aid the dissolving of the C6H12O6 2.5. Place flask with the solution into a water bath set at 35°C 2.6.4. Leave the flask in the water bath until the solution has reached 35°C in order to prevent differences in temperature causing a difference in the results 2.6. Repeat steps 1.1 to 1.51 for each mass of C6H12O6 2.7.5. Always use the same measuring cylinder in order for prevent a difference in results being caused by a difference of material 2.7.6. Make sure that the measuring cylinder is completely dry and that there is no fluid in it before pouring in the H2O in order to ensure a precise measurement of H2O 2. Take one of the labeled flasks out of the water bath

3.7. Check that the solution has reached the right temperature with an digital thermometer precise to two decimal places 3. Pour the solution in to a 50cm3 burette
4.8.7. Make sure that the burette is completely dry and...