Lab 2 Specific Gravity Viscosity CMCE 2351 Lessons

Lab 2: Specific Gravity & Viscosity CMCE 2351

Lessons Learned/Recap • Lab 1 Report due TODAY • Lab 1 - Density • Purpose • Conclusion/Sources of Error

Lab 1 – Conclusions/Errors • • Fluid Thermometer Scale Large Beaker DATA COLLECTED -Temperature -Mass -Volume • Graduated Cylinder • • Eureka Can Small Beaker Object Ruler • Density Bottle (50 m. L) Question: Did the sample sizes impact the experiment?

Lab Structure Class Discussion • Lab Theory (Purpose) • Equipment • Methodology • Outlined in Lab Manual • Data Sheet • Closely follows steps In Groups • Lab Experiment • Results & Sample Calculations • Conclusion/Clean-up • Class Discussion of possible sources of error

Theory (Purpose) • Objective of the laboratory experiment (WHAT is the purpose). • Clearly state what data is to be obtained at the end of the experiment. • Specific Gravity – instrument reading & calculating • Viscosity – observation & calculating

Specific Gravity & Viscosity • Question: Are there units to specific gravity?

Equipment • Two fluids • Thermometer • Scale • Beaker/Graduated cylinder • Hydrometer • • Specific Gravity 2 graduated cylinders 1 steel ball guide Steel balls – two sizes (d 1 = 1. 6 mm, d 2 =3. 2 mm) Stopwatch 4 black timer bands Ruler Sieve Viscosity

Equipment – Hydrometer • Measures Specific Gravity • Works on the principle that a floating body displaces a volume of liquid whose weight is equal to its own For ‘light’ liquid (low S. G. ) • Hydrometer will sink deeper because a greater amount of liquid is required to equal the body’s weight. contrastique. wordpress. com

Equipment – Hydrometer

Methodology/Data Sheet Specific Gravity • Measuring Beaker Method • Determine density of fluid; calculate specific gravity • Take reading on hydrometer Viscosity • Observe difference between fluids and how different size objects move through fluid. • Measure distance & time; calculate viscosity WARNING: Objects will fall VERY fast through the fluids!

Data Sheet – Specific Gravity DATA SHEET Data & Calculations

Data Sheet - Viscosity DATA SHEET Data & Calculations

Typical Values - Viscosity

Calculations - Viscosity Data Calculation Velocity

Calculations - Viscosity • Calculation Kinematic Viscosity

Experiment In Groups • Lab Experiment • Results & Sample Calculations • Conclusion/Clean-up • Class Discussion of possible sources of error REMINDER: Watch your units!

Things to Think About •

Percent Error