2016 · Q26
Match List-I with List-II and select the correct answer using the code given below the Lists:
List I (Element)
- AMg
- BCa
- CSr
- DBa
List II (Property/Use)
- 1Gives red colour to flame
- 2Sulphate compound used in medicine to examine the alimentary canal of a patient
- 3Traps the energy of sunlight in photosynthesis
- 4Control of muscle contraction Code: (a) A B C D 2 4 1 3 (b) A B C D 2 1 4 3 (c) A B C D 3 4 1 2 (d) A B C D 3 1 4 2
General KnowledgeChemistry
- A(a) A B C D 2 4 1 3
- B(b) A B C D 2 1 4 3
- C(c) A B C D 3 4 1 2
- D(d) A B C D 3 1 4 2
Explanation
Magnesium sits at the heart of the chlorophyll molecule, trapping sunlight energy in photosynthesis (A–3); calcium ions control muscle contraction (B–4); strontium salts impart the characteristic crimson-red colour to flames and fireworks (C–1); and barium sulphate, being insoluble and radio-opaque, is swallowed as the "barium meal" to X-ray the alimentary canal (D–2). The code is therefore 3-4-1-2.