(no subject)
Sstoichiometry and Gravimetric Analysis
Procedure:
- Data Table:
Volume of Na2CO3 solution added
Volume of SrCl2 solution added
Mass of dry filter paper
Mass of beaker with paper towel
Mass of beaker with paper towel, filter paper, and precipitate
Mass of precipitate
2. Clean all equipment
3. Weigh filter paper
- Set up a filtering apparatus
- Lable the towel and put in a clean, dry 250mL beaker measure and record mass
- Put 15mL of Na2CO3 into the cylinder and record the volume and pour into the clean, empty beaker
- 25mL SrCl2 record volume and pour into the beaker. Stir the solution with a glass stirring rod
- Measure another 10mL of SrCl2, record volume, add to beaker. Repeat until no precipitate forms
- Once settled, pour the mixture into the funnel. Use the rubber policeman to transfer the precipitate into the funnel
- Rinse the policeman and pour the solution into the funnel, rinse the beaker several more times and pour rinse water into the funnel
- After it is all drained through the funnel, rinse the precipitate on the paper
- Remove filter paper from funnel, place it on the paper towel, unfold filter paper and place it all in the rinsed beaker, place beaker in the drying oven
- Using beaker tongs, remove sample from oven and allow to cool, record mass, dispose the precipitate
- Clean up
MSDS for Na2CO3 :
Safety:
- Wear safety goggles when working around chemicals, acids, bases, flames, or heating devices. Contents under pressure mad become projectiles and cause serious injury.
- Never look directly at the sun through any optical device or use direct sunlight to illuminate a microscope.
- Avoid wearing contact lenses in the lab.
- If any substances gets in your eyes notify your instructor immediately and flush your eyes with running water for at least 15 minutes
- Secure loose clothing, and remove dangling jewelry. Do not wear open-toed shoes or sandals in the lab
- Wear an apron or lab coat to protect your clothing when working with chemicals.
- If a spill gets on your clothing, rinse it off immediately with water for at least 5 min while notifying your instructor.
- Always use caution when working with chemicals
- Never mix chemicals unless specifically directed to do so
- Never taste, touch, or smell chemicals unless specifically directed to do so
- Add acid or base water; never do the opposite
- Ever return unused chemicals to the original container
- Never transfer substances by sucking on a pipette or straw; use a suction bulb
- Follow instructions for proper disposal
- Avoid hearing hair spray or hair gel on lab days
- Whenever possible, use and electric hot plate as a heat source instead of an open flame
- When heating materials in a test tube, always angle the test tube away from yourself and others
- Glass containers used for heating should be made of heat-resistant glass
- Know your school’s fire-evacuation routes
- Clean and decontaminate all work surfaces and personal protective equipment as directed by your instructor
- Dispose of all sharps (broken glass and other contaminated sharp objects) and other contaminated materials (biological and chemical) in special containers as directed by your instructor.