The most common colours in reworks are red, orange, yellow, green, blue, and purple. A student is watching a rework show and sees a set of reworks go off in the order of red, green, purple, and yellow. Identify, in the correct order, the compounds that could have resulted in that set of reworks. Note: More than one answer is possible, but you need to provide only one correct answer.
1- LiCl/ 2- SrCl2 / 3- CaCl2 / 4- NaCl / 5- BaCl2 / 6- CuCl2 / 7- KCl / 8- CsCl
red ___, green ___, purple ____, yellow ____.
(Record your four-digit answer.)