Final answer:
The red tube is used to collect a blood specimen for most blood chemistries, if the green tube is not used. Other tubes have different additives and purposes.
Step-by-step explanation:
The color stopper tube used to collect a blood specimen for most blood chemistries, if the green tube is not used, is the red tube. The red tube contains no additives and is used to collect serum samples for various tests, including blood chemistries. Other tubes, such as the lavender, blue, and yellow tubes, contain different additives and are used for specific purposes.