Match List-I with List—II and select the correct answer using the code given below the Lists : List-I (Element) A. Mg B. Ca C. Sr D. Ba List-iil (Property/ Use) 1. Gives red colour to flame 2. Sulphate compound used in medicine to examine the alimentary canal of a patient 3. Traps the energy of sunlight in photosynthesis 4. Control of muscle contraction Code :

The elements of Group 2 (alkaline earth metals) exhibit distinct properties and biological roles. Magnesium (A) is a central component of chlorophyll, which is essential for trapping sunlight energy during photosynthesis. Calcium (B) is critical for biological structures and physiological processes, specifically playing a vital role in the control of muscle contraction. Strontium (C) is known for its characteristic flame test, where its salts burn with a bright red color, making it useful in fireworks and flares. Barium (D), specifically in the form of barium sulfate, is used as a radiopaque contrast agent (barium meal) to examine the alimentary canal or digestive tract via X-rays because it is insoluble and blocks radiation [1]. Matching these properties (A-3, B-4, C-1, D-2) leads to Option 3.

Sources

1. [1] https://www.sciencedirect.com/topics/medicine-and-dentistry/barium-ion