Answer:
Explanation:
We can use the Noyes-Whitney equation to calculate the rate of dissolution.
Data:
D = 1.75 × 10⁻⁷ cm²s⁻¹
A = 2.5 × 10³ cm²
Cₛ = 0.35 mg/mL
C = 2.1 × 10⁻⁴ mg/mL
d = 1.25 µm
Calculations:
Cₛ - C = (0.35 - 2.1 × 10⁻⁴) mg·cm⁻³ = 0.350 mg·cm⁻³
d = 1.25 µm = 1.25 × 10⁻⁶ m = 1.25 × 10⁻⁴ cm
Those would be called indicators , simply google them and you should find many. I'll leave some examples "bromophenol blue" "Methyl red" and "phenol red".