Question

Orange juice stored under ambient conditions shows vitamin C degradation following first-order kinetics with degradation constant \(k = 5.2 \times 10^{-3} \ \text{day}^{-1}\). What is the half-life of vitamin C in days (integer)?

Hint:

For first-order degradation: half-life depends only on the rate constant, not on the concentration.

Answer 1

Step 1: Formula for half-life in first order kinetics.
\[ t_{1/2} = \frac{0.693}{k} \] Step 2: Substitute values.
\[ t_{1/2} = \frac{0.693}{5.2 \times 10^{-3}} = \frac{0.693}{0.0052} \] \[ t_{1/2} \approx 133.3 \ \text{days} \] \fbox{Half-life = 133 days}