Question

A pharmacist dissolved a few milligrams of a new antibiotic drug into exactly 100 mL of distilled water and placed the solution in a refrigerator (5°C). At various time intervals, the pharmacist removed a 10-mL aliquot from the solution and measured the amount of drug contained in each aliquot. The following data were obtained:

Time (hours)	Antibiotic (μg/mL)
0.5	84.5
1.0	81.2
2.0	74.5
4.0	61.0
6.0	48.0
8.0	35.0
12.0	8.7

1. Is the decomposition of this antibiotic a first-order or a zero-order process?

2. What is the rate of decomposition of this antibiotic?

3. How many milligrams of antibiotics were in the original solution prepared by the pharmacist?

4. Give the equation for the line that best fits the experimental data

Answer 1

a) this decomposition is a zero order process as rate of reaction is a constant = k

[A(t)] = [A(0)] - k t

slope of linear fit gives rate of reaction = 6.59 micro gram ml^-1hr^-1

at t = 0 hr original solution had 87.665 x 100 = 8766.5 micro grams = 8.7665 milligrams of antibiotics

A = 87.665 - 6.59 t

please rate it up thanks :)