Sodium chloride is a metal chloride which is soluble in cold water - Edexcel - GCSE Chemistry - Question 5 - 2013 - Paper 1

Sodium chloride has a high melting point of 801 °C due to strong ionic bonds between sodium (Na⁺) and chloride (Cl⁻) ions. These ionic bonds result from the strong electrostatic forces of attraction between the positively charged sodium ions and negatively charged chloride ions. To melt sodium chloride, a considerable amount of energy is required to overcome these strong ionic bonds, which contributes to its high melting point.

To test for the presence of chloride ions in a sodium chloride solution, you would add a few drops of dilute nitric acid (HNO₃) to the solution to remove any other ions present. Then, add a few drops of silver nitrate (AgNO₃) solution. If chloride ions are present, a white precipitate of silver chloride (AgCl) will form, indicating a positive test for chloride ions. The reaction can be summarized as:

$Ag^+ (aq) + Cl^- (aq) \rightarrow AgCl (s)$