Lab Manual 1 - SIGNIFICANT FIGURES AND TECHNIQUE EXPERIMENT...

Info iconThis preview shows pages 1–4. Sign up to view the full content.

View Full Document Right Arrow Icon
1 SIGNIFICANT FIGURES AND TECHNIQUE EXPERIMENT 1 INTRODUCTION In this experiment you will be taught a few techniques that will be needed throughout the remainder of the course. By the end of the laboratory period, you should be able to get reliable data using the analytical balance, a pipet, a buret, a graduated cylinder and a volumetric flask. You should also be able to write down readings and calculated values with the correct number of significant figures. Finally, you should as well be able to wash, rinse and dry laboratory glassware. Before performing any experiment you must have attended a safety lecture in the lab and completed the safety exercise. If you have not done this, see JM Gauthier room #3 inside the lab), before your regularly scheduled lab day. APPARATUS AND CHEMICALS Apparatus and glassware Thermometer Dropper Electronic balance Pipet & bulb Buret 50 mL volumetric flask & stopper (3) 50 mL beaker (2) 100 mL beaker (2) 800 mL beaker 25 mL graduated cylinder Chemicals Acetone Distilled water Unknowns
Background image of page 1

Info iconThis preview has intentionally blurred sections. Sign up to view the full version.

View Full DocumentRight Arrow Icon
2 THEORY This section gives detailed instructions on how to use the analytical balance, pipet, buret, graduated cylinder and volumetric flask. When reading, keep in mind that a demonstration will be performed in the Lab. You will also find explanations on the concepts of precision, accuracy and significant figures. Analytical balance buret pipet Graduated Volumetric flask cylinder The analytical balance The Mettler AE 100/200 electronic balances have no weights and the actual balancing is done by an electronic circuit. The balance functions are controlled by a single bar which is located along the front of the balance. This bar acts as an on/off switch and as a zero or adjusting switch. Above the control bar is a digital display window which shows the weight currently being measured by the balance. Precautions when weighing Keep the balance clean. Do not weigh chemicals directly on the pan. Use a small container or a vial. Do not handle object being weighed directly with your bare hands, use gloves or a piece of clean paper. Dirt or grease from the fingers will change the mass of the object. Allow all objects or chemicals to attain room temperature before weighing, otherwise convection currents will cause errors. Perform all operations slowly and gently. The balance is a costly precision instrument and must be treated with utmost care for it to continue functioning to its capability.
Background image of page 2
3 Operating procedure for Weighing on a Mettler AE100/200 balance 1. Check that the pan is clean and all the sliding windows are closed. 2. Switching the balance on: Briefly press the control bar. All display elements light up for several seconds; this permits a functional check of the display, then 0.0000 is displayed.
Background image of page 3

Info iconThis preview has intentionally blurred sections. Sign up to view the full version.

View Full DocumentRight Arrow Icon
Image of page 4
This is the end of the preview. Sign up to access the rest of the document.

Page1 / 18

Lab Manual 1 - SIGNIFICANT FIGURES AND TECHNIQUE EXPERIMENT...

This preview shows document pages 1 - 4. Sign up to view the full document.

View Full Document Right Arrow Icon
Ask a homework question - tutors are online