What does To Contain (TC) mean in laboratory glassware specifications?

• A. The container is made to hold exactly the volume printed on the container.
• B. The device is used to calibrate thermometers against standards.
• C. The glassware is classified as Class A or Class B.
• D. The container is designed to deliver that exact amount into another container.

Answer: (A)

To Contain means the vessel is made so that its stated volume is the actual amount it will hold when filled to the calibration mark. In other words, its capacity equals the printed volume at the standard reference temperature (usually 20°C). This is why volumetric glassware used for making standard solutions is described as TC: you fill to the mark and the liquid inside is that exact volume. It differs from devices calibrated to deliver a precise amount when you pour from them; those are described as To Deliver, where the emphasis is on the amount dispensed. The other options don't fit because they refer to different ideas—thermometer calibration, a quality class designation, or delivering volume into another container rather than containing the exact amount inside.