Alkane Viscosity Experiment Viscosity of Alkanes Experiment First

Alkane Viscosity Experiment

Viscosity of Alkanes Experiment • First Experiment: – Measured viscosity using marble drop – Timed from 80 m. L to 30 m. L – Problems? • Timing difficult (marble too fast) • Marble may have variable weight • Others? • Further Experiments: – More reliable timing data – Determine the effect of marble mass on data collection

Alkane Viscosity • Further Experiments: – More reliable timing data • Measure time over longer distance (100 m. L? ) • Perform more trials to ensure consistency and discard outlying data – Determine the effect of marble mass on data collection • Perform trials of 1 oil using different marbles to ensure that data collection is unaffected • Provides evidence to defend experimental setup when presenting findings

Alkane Viscosity • Three additional experiments 1. Re-do previous experiment with 100 m. L distance 2. Perform marble drop with 1 oil, using 5 different marbles (mass each first) at 3 trials each 3. Determine density of each oil to establish a correlation (or lack thereof) between density and viscosity

Alkane Viscosity Report • Data Tables (typed) of all collected data for all experiments – 50 m. L drop experiment, 9 oils x 3 trials each (+ avg. time for each = 36 data points) – 100 m. L drop expt, 9 oils x 3 trials each (+ avg. time for each = 36 data points) – Marble mass expt, 5 marbles x 3 trials each (1 oil for total of 20 data points) – Density, 6 oils (expressed as g/m. L) • Make sure that tables are clearly labeled and organized logically

Alkane Viscosity Report • Graphs 1. 50 m. L drop: graph average drop time for each oil 2. 100 m. L drop: graph avg. drop time for each oil 3. Superimpose both graphs with different colors for each line (double 50 m. L data) 4. Marble mass: graph average time for each marble 5. Density: graph density for each oil 6. Graph density vs. 100 m. L drop time

Analysis • After creating tables and graphs, analyze available data • Possible questions to consider: – Was the 100 m. L drop data more reliable than the 50 m. L drop? How can you tell? – Does the mass of the marble affect drop time? Is it significant enough to alter our experimental design? – Is there a correlation between oil density and viscosity (i. e. drop time)? – If density does not explain viscosity, then what other experiments could be done in the future? – Consider other questions…what does the data indicate? What does it NOT indicate?

Lab Report Write-Up • Organized tables and graphs • Analysis section • Error Analysis – What were problems with the experimental design? – For what variables have we NOT accounted? – In collecting your data, what errors may have occurred? – How reliable is your data?

Scoring • Your grade for the write-up will be determined by the following factors – Organization and clarity – Logical flow to analysis/error analysis • Don’t answer each question individually • The answers should all be presented together as part of your overall analysis – Thorough consideration of questions in analysis and error analysis sections – Consideration of other factors/questions