Which change represents an increase in the entropy system

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 →

7. what temperature is need to just dissolve 50 g of nh4cl in 75 g of water? '

In which phase(s) do the molecules take the shape of the container?