explain the process of preparation of olfactory indicator using onion and clean cloth
Answers
Olfactory Indicators is a substance whose smell depending on whether it is mixed with an acidic or basic solution. odour can be deleted in bases where as odour remains same in acidic solution.
1. Put some finely chopped onions in a plastic bag along with same clean cloth. tie up the bag tightly and keep it overnight in the fridge.
2. Check the odour of the cloth strips.
3. Keep two strips on a clean surface and put a few drops of Dilute HCI on one strip and a few drops of Dilute NaOH on the other.
4. Rinse both the strips separately with distilled water and again check their odour and note the observation.
An Acidic solution like Hydrochloric acid is added to the cloth strip does not destroy the smell of onions. when a basic solution like Sodium Hydroxide solution is added to a cloth strip treated with onion extract then the onion smell cannot be deleted.
5. Take some clove oil and Vanilla Essence.
6. Take some Dilute HCI in one test tube and Dilute NaOH in another test tube. Add a drop of Dilute Vanilla Essence to both test tubes and stir well with glass rod.
: The odour of Vanilla is no change when we added acid (HCI).
: The odour of Vanilla is deleted when we added base (NaOH).
7. Test the change odour of clove oil using Dilute HCI Dilute NaOH.
Clove oil with acid: No change in Odour.
Clove oil with Base: No Odour.
Onions, Vanilla Essence and Clove oil can be used as a Olfactory Indicators.
Olfactory Indicators are useful for those who are visually Impaired to identify acids and alkalis.
Answer:
expain the process of preparation of olfactory indicator using onion and clean cloth