Flame and Air Adjustment
USE OF EQUIPMENT
SAFETY PRECAUTIONS:
1. Wear lab coats and safety goggles.
2. Tie back hair and loose clothing.
3. Be careful with burner and matches.
4. Be careful with glass.
5. Do not leave burner flame unattended.
PROCEDURE:
A. Lighting a Burner (see page 7)
1. Close air adjustment. Open air adjustment by rotating barrel 2 times.
2. Close gas adjustment valve. Open gas adjustment valve at least 2 times.
3. Strike match and hold flame at the top of the burner.
4. Turn gas on at main gas valve.
5. Adjust height of flame to 8-10 cm. (flame may be yellow or blue.)
6. Close air vents for luminous yellow flame. Open the air adjustment for blue and double-cone blue flames.
7. Draw burner and label parts.
Problems:
If flame is too short when outlet is fully open, use gas adjustment valve. If flame drops into barrel, air vents are open too wide. If flame blows out, gas adjustment valve or air vents are open too much.
B. Reading a Graduated Cylinder (See page 10)
1. Obtain graduated cylinder containing water and place on a flat surface at eye level.
2. Place a darker object behind the meniscus and read the liquid level at the lowest point on the meniscus.
3. If a 50 or 100 mL cylinder is used, the smallest subdivision will be ones or units. The volume should be estimated to the tenths.
4. Draw graduated cylinder and meniscus.
5. Report quantity with correct value, to tenths position, with the appropriate units.
C. Reading a Balance (See pages 9-10)
1. Place all three riders in the zero position, and set the pointer on zero.
2. Place mass on pan. Use container when necessary – no chemicals directly on pan.
3. Move rider with greatest mass (100 g increments) until pointer drops below zero, then slide rider back one notch. The quantity is between these two values.
4. Repeat step 3 using the rider with the next greatest mass (10g increments)
5. Move the smallest rider until the balance pointer is on zero.
6.
SAFETY PRECAUTIONS:
1. Wear lab coats and safety goggles.
2. Tie back hair and loose clothing.
3. Be careful with burner and matches.
4. Be careful with glass.
5. Do not leave burner flame unattended.
PROCEDURE:
A. Lighting a Burner (see page 7)
1. Close air adjustment. Open air adjustment by rotating barrel 2 times.
2. Close gas adjustment valve. Open gas adjustment valve at least 2 times.
3. Strike match and hold flame at the top of the burner.
4. Turn gas on at main gas valve.
5. Adjust height of flame to 8-10 cm. (flame may be yellow or blue.)
6. Close air vents for luminous yellow flame. Open the air adjustment for blue and double-cone blue flames.
7. Draw burner and label parts.
Problems:
If flame is too short when outlet is fully open, use gas adjustment valve. If flame drops into barrel, air vents are open too wide. If flame blows out, gas adjustment valve or air vents are open too much.
B. Reading a Graduated Cylinder (See page 10)
1. Obtain graduated cylinder containing water and place on a flat surface at eye level.
2. Place a darker object behind the meniscus and read the liquid level at the lowest point on the meniscus.
3. If a 50 or 100 mL cylinder is used, the smallest subdivision will be ones or units. The volume should be estimated to the tenths.
4. Draw graduated cylinder and meniscus.
5. Report quantity with correct value, to tenths position, with the appropriate units.
C. Reading a Balance (See pages 9-10)
1. Place all three riders in the zero position, and set the pointer on zero.
2. Place mass on pan. Use container when necessary – no chemicals directly on pan.
3. Move rider with greatest mass (100 g increments) until pointer drops below zero, then slide rider back one notch. The quantity is between these two values.
4. Repeat step 3 using the rider with the next greatest mass (10g increments)
5. Move the smallest rider until the balance pointer is on zero.
6.