Which one of the following Acids is used as bathroom cleaner and is also present in gastric juices that are responsible for digestion?
Answer & explanation
Correct answer: option 3
The correct answer is Option (3) → Hydrochloric Acid
The wall of the stomach secretes hydrochloric acid into the gastric juice. It kills germs in the food and makes the medium acidic, which the enzyme pepsin needs to digest proteins. Dilute hydrochloric acid, sold as muriatic acid, is also used to clean toilets and bathroom tiles because it dissolves hard-water and lime-scale stains.
Why the other options are incorrect
Option (1) Nitric Acid — Incorrect. A strong acid used to make fertilisers and explosives; it is not part of gastric juice.
Option (2) Boric Acid — Incorrect. A weak acid used as a mild antiseptic (eyewash) and as an insect-killing powder.
Option (4) Phosphoric Acid — Incorrect. Used in fertilisers, cola drinks and rust removers, but the stomach does not secrete it.