Why are chemical changes considered “unseen”?

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 →

200. ml of 3.00 m nacl solution is diluted to a final volume of 500. ml. what is the molarity of the final solution?

What are transitions between a liquid and gas called? identify which way they are transitioning