American Chemical Society (ACS) Laboratory Safety Test 2025 – 400 Free Practice Questions to Pass the Exam

In a dry-ice bath, the preferred liquid is acetone. Using acetone in a dry-ice bath optimizes the cooling capabilities necessary for many laboratory applications. Acetone has a low freezing point (around -95 °C), making it effective for achieving lower temperatures when combined with dry ice. This enables quicker cooling of samples or materials placed within the bath.

While isopropyl alcohol is a common cooling medium, it has a higher freezing point compared to acetone (approximately -89 °C). Therefore, while it can effectively cool, it does not achieve the same low temperatures as acetone under similar conditions. The other options, such as water and ethyl acetate, would not be as effective in achieving the desired cooling temperatures for applications requiring a dry-ice bath. Water, in particular, can freeze and become ineffective in providing the desired low-temperature environments. Ethyl acetate may not be suitable either, as it has a higher freezing point compared to acetone, leading to less efficient cooling capabilities.