Why distilled water added to the R- tube in this experiment?

Why distilled water added to the R- tube in this experiment?

• A. To dissolve enzyme
• B. To increase ionic strength
• C. Acts as a control for volume/weight balance
• D. To inactivate enzyme

Answer: (C)

Matching the final liquid volume across tubes is essential for fair comparisons. When tubes have different volumes, the same enzyme or substrate can produce different signals simply because the reaction mixture is more or less diluted, altering readings like absorbance or reaction rate. Adding distilled water to the R- tube keeps its total volume the same as the other tubes, so any differences you observe come from the enzyme's activity rather than extra liquid. The water serves as a neutral filler that balances volume and weight without introducing new reagents or changing the chemical environment in a way that would confound the results.

Matching the final liquid volume across tubes is essential for fair comparisons. When tubes have different volumes, the same enzyme or substrate can produce different signals simply because the reaction mixture is more or less diluted, altering readings like absorbance or reaction rate. Adding distilled water to the R- tube keeps its total volume the same as the other tubes, so any differences you observe come from the enzyme's activity rather than extra liquid. The water serves as a neutral filler that balances volume and weight without introducing new reagents or changing the chemical environment in a way that would confound the results.