Science : Ch 02 – Acids Bases and Salts

Clove oil is an olfactory indicator. These the substances which give one type of odour in acidic medium and a diferent odour in basic medium so a visually challenged student favours to use clove oil as an acid-base indicator.

Citric acid is not a mineral acid. It is an organic acid or edible acid that is obtain from organic compounds

Baking powder is a mixture of sodium hydrogen carbonate and tartaric acid NaHCO₃ + H+ → CO₂ + H₂O + Sodium salt (from tartaric acid) of acid Carbon dioxide (CO₂) produced during reaction can cause bread or cake to rise and makes Baking powder, tartaric acid neutralises the salt and cake does not taste bitter.

Chemical name of plaster of Paris is calcium sulphate hemihydrate. It is written in this form because two formula units of CaSO₄ share one molecule of water.

Acids turn blue litmus solution to red. They have a sour taste as in the case of vinegar and are sticky to touch. On the other hand, bases turn red litmus solution to blue. Bases are bitter in taste as in the case of baking soda and are slippery to touch.

C₂H₅OH is not a base. C₂H₅OH is an organic compound with –OH functional group that is known as alcohol

Common salt (NaCl) is formed after a reaction between hydrochloric acid (HCl) and sodium hydroxide (NaOH)

On a pH scale acidity ranges from 1 to 7 and it increases by moving down from 7 to 1 while basicity ranges from 7 to 14 which increases by moving up from 7 to 14.

HCI, being a polar covalent compound, easily ionses in water to form hydronium (H₃O+) and chloride ions (Cl– ). HCl (a strong acid) ionises completely in water to produce H+ and Cl–  ions. H+ ion dilutes with water molecules to produce hydronium ions.

When the pH of an aqueous solution is higher, its acidic properties are weak. Thus, it is a base. When the pH an aqueous solution is lower, its basic properties are weak. Thus, it is an acid.