Today, after spending some time using a lightbulb to test electrolytes and non-electrolytes, we carried out a qualitative analysis scheme to determine the identity of an unknown substance. After the lab I shared the following observations:
- Carry out tests on known substances before testing unknown substances.
- Be methodical in testing, use charts and try many possible combinations of substances. Carefully record all observations.
- The scheme provided is not the only way to solve a qualitative problem – it is one way. It is fine to try other tests – if you are unsure about the safety of a test then please ask me about it.
Reminders about using the laboratory notebook:
- Use INK not pencil
- Record ALL data and observations directly into the notebook – do not recopy
- No erasures, no white out – one line through mistakes
- Record during laboratory as part of the process.
We worked for an hour after lab on classifying types of chemical reactions, balancing reactions and beginning stoichiometery. We will continue to work on problems in stoichiometery.
Assignments collected so far:
- First laboratory – Laboratory Techniques (last Thursday)
- Student Interview
- KNEX activity (today)
- Student Safety Contract (Emergency Contact Form)
- Laboratory Equipment Inventory (Place in your drawer.)
Homework:
Fill out the Student Interview if you have not already done so.
Work on homework assignments 1-6.
Continue to study the names of the polyatomic anions.
Research the answer to the question:
What chemical is produced in this country more than any other and why?