Answer: They are mild bases that neutralise excess stomach acid gently without damaging the stomach lining.
- A They work mainly by reducing the bacteria responsible for producing stomach acid
- B They lower stomach pH well below neutral, making the stomach somewhat more acidic afterward
- C They react slowly with hydrochloric acid present in the stomach, so they take longer to act
- D They are mild bases that neutralise excess stomach acid gently without damaging the stomach lining
Correct answer: D. They are mild bases that neutralise excess stomach acid gently without damaging the stomach lining
Explanation: Antacids such as aluminium and magnesium hydroxide are mild bases that neutralise excess stomach acid gradually, unlike a strong base, which could harm the stomach lining.
The hydrophobic hydrocarbon tail of each soap/detergent molecule dissolves into an oily dirt droplet, while the hydrophilic (ionic) head stays in the surrounding water - trapping the grease inside a micelle that rinses away with water.
Concept context
Drugs and how they interact with biological targets, chemicals in food, and cleansing agents (soaps and detergents) - chemistry applied directly to daily life and healthcare.