A solution of concentrated aqueous ammonia 18 dded dropwise to 1 mL of a dilute aqueous solution of copper (II) nitrate until a total of 1 mL of the ammonia solution has been added. What observations can be made during this process?

The light blue copper (II) nitrate solution turns dark blue and yields a dark blue precipitate.

The light blue copper {II) nitrate solution yields a precipitate which redissolves to form a dar blue solution.

The colourless copper {II) nitrate solution turn 8 blue and yields a dark blue precipitate.

The colourless copper (II) nitrate solution yields a white precipitate which turns dark blue upon standing.