Electronic Top-Loading Balance
General Instructions
The usual operation of an electronic top-loading balance is quite simple. The instructions for the usual operation and for some variations are listed here and in Example 8 in your workbook. This type of balance can weigh things to three decimal places. That is, it will weigh to the nearest thousandth of a gram. It should be left on at all times. When you're through using it, leave it on. If the components of an electronic balance are cold when you start, they will drift while warming up, causing changes in your measurements. Leaving it on so it stays warm will avoid this.
 |
Start by placing a container on the balance pan. Then press the TARE button. Wait for the "U -----" to disappear. |
 |
That sets the balance to weigh anything that is placed into the container, but it does not weigh the container itself. When the "U" has disappeared and "0.000" shows in the display, it is time to add what you want to weigh to the dish. |
 |
After the material has been added to the container, the "U" will appear again while the material is being weighed. |
 |
When the "U" disappears record the weight of the material in the container. |
 |
Then remove the container, clean up any spills, reset the balance to zero, and close the cover. |
Now, again weigh a sample and and record its weight in the table in Exercise 9. Have the instructor check your measurement.