CWEA Grade 1 Laboratory
Analyst – 50 Q&A
General Laboratory Safety
1. Q: Why is wearing safety goggles important in a lab?
A: To protect eyes from chemical splashes and debris.
2. Q: What should you do if a chemical spill occurs?
A: Notify others, follow spill procedures, and clean it using proper PPE.
3. Q: What does MSDS (or SDS) stand for?
A: Material Safety Data Sheet (Safety Data Sheet).
4. Q: Why should food and drink be prohibited in the lab?
A: To prevent contamination and chemical ingestion.
5. Q: What type of fire extinguisher is commonly used in labs?
A: Class ABC fire extinguisher.
Units, Measurements, and Math
6. Q: How many milliliters are in 1 liter?
A: 1,000 mL.
7. Q: Convert 0.5 liters to milliliters.
A: 500 mL.
8. Q: What does ppm stand for?
A: Parts per million.
9. Q: In water analysis, 1 ppm is approximately equal to what unit?
A: 1 mg/L.
10. Q: What is the formula for percent (%)?
A: (Part ÷ Whole) × 100.
Glassware and Equipment
, 11. Q: Which glassware is most accurate for measuring volume?
A: Volumetric flask or pipette.
12. Q: What is a graduated cylinder used for?
A: Measuring liquid volume.
13. Q: What instrument measures pH?
A: pH meter.
14. Q: What is the purpose of a balance?
A: To measure mass.
15. Q: Why should glassware be clean before use?
A: To avoid contamination and inaccurate results.
Sampling and Preservation
16. Q: Why are samples preserved?
A: To prevent biological or chemical changes.
17. Q: What preservative is commonly used for nutrient samples?
A: Sulfuric acid.
18. Q: What does “chain of custody” mean?
A: Documentation tracking sample handling.
19. Q: Why is refrigeration used for samples?
A: To slow biological activity.
20. Q: What is a grab sample?
A: A single sample collected at one time.
pH and Alkalinity
21. Q: What is the pH range of wastewater typically?
A: 6.0 to 9.0.
22. Q: What does pH measure?
A: Acidity or alkalinity.
23. Q: A pH of 7 is considered what?
A: Neutral.
Analyst – 50 Q&A
General Laboratory Safety
1. Q: Why is wearing safety goggles important in a lab?
A: To protect eyes from chemical splashes and debris.
2. Q: What should you do if a chemical spill occurs?
A: Notify others, follow spill procedures, and clean it using proper PPE.
3. Q: What does MSDS (or SDS) stand for?
A: Material Safety Data Sheet (Safety Data Sheet).
4. Q: Why should food and drink be prohibited in the lab?
A: To prevent contamination and chemical ingestion.
5. Q: What type of fire extinguisher is commonly used in labs?
A: Class ABC fire extinguisher.
Units, Measurements, and Math
6. Q: How many milliliters are in 1 liter?
A: 1,000 mL.
7. Q: Convert 0.5 liters to milliliters.
A: 500 mL.
8. Q: What does ppm stand for?
A: Parts per million.
9. Q: In water analysis, 1 ppm is approximately equal to what unit?
A: 1 mg/L.
10. Q: What is the formula for percent (%)?
A: (Part ÷ Whole) × 100.
Glassware and Equipment
, 11. Q: Which glassware is most accurate for measuring volume?
A: Volumetric flask or pipette.
12. Q: What is a graduated cylinder used for?
A: Measuring liquid volume.
13. Q: What instrument measures pH?
A: pH meter.
14. Q: What is the purpose of a balance?
A: To measure mass.
15. Q: Why should glassware be clean before use?
A: To avoid contamination and inaccurate results.
Sampling and Preservation
16. Q: Why are samples preserved?
A: To prevent biological or chemical changes.
17. Q: What preservative is commonly used for nutrient samples?
A: Sulfuric acid.
18. Q: What does “chain of custody” mean?
A: Documentation tracking sample handling.
19. Q: Why is refrigeration used for samples?
A: To slow biological activity.
20. Q: What is a grab sample?
A: A single sample collected at one time.
pH and Alkalinity
21. Q: What is the pH range of wastewater typically?
A: 6.0 to 9.0.
22. Q: What does pH measure?
A: Acidity or alkalinity.
23. Q: A pH of 7 is considered what?
A: Neutral.
