Photo AI
This question is about sodium chloride and iodine - AQA - GCSE Chemistry - Question 6 - 2015 - Paper 2
Question 6
This question is about sodium chloride and iodine. 6 (a) Describe the structure and bonding in sodium chloride. 6 (b) When sodium chloride solution is electrolysed... show full transcript
Worked Solution & Example Answer:This question is about sodium chloride and iodine - AQA - GCSE Chemistry - Question 6 - 2015 - Paper 2
Step 1
6 (a) Describe the structure and bonding in sodium chloride.
Answer
Sodium chloride (NaCl) has a cubic lattice structure, characteristic of ionic compounds. It consists of positively charged sodium ions (Na⁺) and negatively charged chloride ions (Cl⁻) arranged in a three-dimensional grid. The bonding occurs due to the electrostatic attraction between these oppositely charged ions, which forms a strong ionic bond.
Step 2
Step 3
Step 4
6 (d) (i) Complete Figure 4 to show the bonding in iodine. Show the outer electrons only.
Answer
In Figure 4, each iodine atom (I) should be represented with its outer electrons shown as dots around the symbol. Since iodines bond covalently, each iodine atom will share one electron with the other, resulting in a pair of shared electrons between the two iodine atoms.
Step 5
6 (d) (ii) Explain why iodine has a low melting point.
Answer
Iodine has a low melting point because it consists of simple molecular structures with weak van der Waals forces between the molecules. These intermolecular forces are much weaker than ionic or covalent bonds and require only a small amount of energy to overcome, resulting in a low melting point.
Step 6
6 (d) (iii) Explain, in terms of particles, why liquid iodine does not conduct electricity.
Answer
Liquid iodine does not conduct electricity because it consists of neutral iodine molecules that do not possess free or mobile electrons. Since there are no charged particles available to carry electric current in the liquid state, it remains non-conductive.