¿Si se forman nuevas sustancias en una reacción, también se está formando nueva materia?

This chart represents the melting point of several substance. what besy explains the high melting point of the salt?

1. combine iron and copper (ii) sulfate solution. (hint: iron will form the iron (iii) ion) fe + cuso4 → 2. combine lead (ii) nitrate and potassium iodide solutions. pb(no3)2+ kl → 3. combine magnesium metal and hydrochloric acid solution. mg + hcl → 4. electrolysis (splitting) of water. h2o → 5. burning magnesium. mg + o2 →

Substance x has a fixed volume, and the attraction between its particles is strong .substance y had widely spread out particles and can be compressed what can most likely be concluded about these substances