Recipe
Aqueous version
- Add 0.1g Bromthymol blue into 16ml of 0.01N NaOH
- Mix in a mortar or small tube
- Dilute to 250ml with distilled water
- Use 5 drops in 10ml of test solution
Alcohol version
- Add 0.5g of Bromthymol blue into 500ml of 95% ethanol and dissolve
- Add 500ml of distilled water
- Filter and store at room temperature
