Laboratory Assignment: Using a Top Loading Balance
1.How is the balance turned on?
To turn on the top loading balance, press down on the bar that is on the front of the machine. 2. Write a complete and accurate procedure for weighing a chemical on the top loading balance. To weigh a chemical using the top loading balance, follow these steps: a. Press the bar on the front of the machine to turn on the balance b. Wait for the digital display to read “0.00 g” (grams) c. Place a weighing paper on the pan of the balance
d. Zero out the scale by pressing the bar on the front of the machine e. Using the paper to hold the substance, place the solid chemical on the pan to be weighed f. Check the display for the mass of the chemical (grams)
3. Identify two things that can go wrong when using the procedure in item 2 above. Using the procedure for the top loading balance listed in #2 may result in inaccuracies or accidents. The top loading balance in general is not the most accurate machine to use when determining the weight of a chemical. An analytical balance digital display is more accurate than a top loading balance in measuring to more places after the decimal point. Also, chemicals left loose on the weighing paper are subject to temperature, humidity, and air changes in the room. When using the method listed above for the top loading balance, accidents can readily occur that may cause harm to people and property. 4. What is the role of the weighing paper in this procedure? What potential risks might be present if the weighing paper is not used? The weighing paper is used to protect the pan on the top loading balance from the chemicals being weighed. Chemicals inadvertently left on the pan from a previous measurement may result in not only inaccurate measurements, but these chemicals may have harmful reactions if unplanned contact occurs with each other. 5. What is the mass of the chemical in grams in the above procedure? The mass of the chemical measured in the...
Please join StudyMode to read the full document