Which pair of elements are both malleable metals and good conductors of electricity?

Introduction / Context:
In basic chemistry and physics, metals are often described as malleable and good conductors of heat and electricity. Non metals and noble gases, by contrast, usually lack these properties. This question tests whether you can correctly identify which pair of elements from the options are metals that show the typical metallic properties of malleability and good electrical conductivity.

Given Data / Assumptions:
- Tin and silver are both well known metallic elements.
- Iodine is a halogen non metal and xenon is a noble gas.
- Malleability means the ability to be hammered or rolled into thin sheets without breaking.
- Good electrical conductivity is a characteristic property of metals.

Concept / Approach:
Metals have a structure in which outer electrons are relatively free to move, forming an electron sea that allows electrical conduction and some plastic deformation under stress. This gives rise to properties like malleability and good electrical conductivity. Tin is a soft, malleable metal used in alloys and coatings. Silver is a metal with very high electrical conductivity, better than copper in pure form. Iodine, on the other hand, is a non metal that forms crystals and does not show metallic malleability or high electrical conductivity. Xenon is a noble gas, existing as isolated atoms under normal conditions, and is neither malleable nor a conductor in the solid metallic sense.

Step-by-Step Solution:
Step 1: Identify tin as a metal in the periodic table, with metallic bonding and typical metallic properties. Step 2: Identify silver as a metal, widely used for jewellery and electrical contacts due to its excellent conductivity. Step 3: Recognise that iodine is a halogen non metal with molecular crystals at room temperature, not malleable and not a good conductor. Step 4: Recognise that xenon is a noble gas and exists as a gas of isolated atoms, not as a solid metal. Step 5: Conclude that the only pair where both elements are malleable metals and good conductors is tin and silver. Step 6: Therefore, option A is the correct answer.

Verification / Alternative check:
You can check typical uses of each element. Tin is used in solder and tinplate, which require malleability and decent conduction. Silver is used in electrical contacts, high quality connectors and jewellery, all of which rely on its metallic properties. Iodine finds use in medicine and as a disinfectant, not as a structural metal. Xenon is used in lamps and special gas mixtures, again not as a solid metal. These applications confirm which elements are metallic and which are not.

Why Other Options Are Wrong:
Iodine and silver: Only silver is a malleable, highly conductive metal; iodine is a non metal.
Tin and xenon: Tin is a metal, but xenon is a noble gas and not a malleable conductor.
Iodine and xenon: Both are non metallic in their usual forms, so neither is a malleable conductor of electricity like a metal.

Common Pitfalls:
Learners sometimes focus only on one element in a pair, such as silver being a well known conductor, and ignore the nature of the second element. It is crucial to check both elements in the pair. Another source of confusion is assuming that any element associated with lighting or technology, such as xenon in lamps, must be metallic, which is not true. Always check the position of the element in the periodic table and its bonding type.

Final Answer:
The pair where both elements are malleable metals and good conductors of electricity is tin and silver.