AP Chemistry – Class 13
Date – Friday, September 18th
Analysis of an Alloy – Lab02
The lab is an example of quantitative analysis, where we use a precipitation reaction to determine the composition of a solid. Besides reading the instructions for the lab, there are a few pointers that need to be heeded:
- pipette skills – when dispensing very string acids, it is necessary to use a pipette and bulb
- safety with acid – care should be taken to be safe when using acids, with a neutralizer at the ready in case of spillage
- weigh boats for everything – when using an analytical balance, it is necessary to use weigh boats to eliminate contamination
- drying oven – be sure and place the crucible in the drying oven after the initial washing and after forming the PPT.
- be sure and use only distllied water when washing glassware, and wash everything
The lab will be done in two days: the first part will be done during class on Friday. The second part will be done during office hours, before or after school (or lunch) on Monday or Tuesday. The final massing of the PPT will be done before class on Wednesday.The calculations will be done before class on Wednesday for discussion.
- Monday class – wash crucible leave in oven, mass alloy, react alloy, PPT with NaCl
- Before Tuesday – filter PPT, dry in oven, find mass of crucible with contents
- Tuesday – discuss results / work on report
- Lab Report Due – Friday, September 25
- Nicely written in LNB
- Data / Calcs / Analysis / Conclusion