Which of the following describes the physical state of formaldehyde?

Formaldehyde is best described as a colorless gas at room temperature, which aligns with the correct answer. It has a distinctive, pungent odor and is commonly used in various industrial applications and as a preservative in laboratories and funeral homes. When it is combined with water, it typically forms a liquid solution known as formalin, which is around 37% formaldehyde in water. However, in its pure state, formaldehyde vaporizes as a gas.

Understanding its physical state is crucial for professionals working with this compound, especially in areas related to safety, storage, and application. Knowing that formaldehyde is a gas helps in recognizing the need for proper ventilation and handling practices to minimize exposure, as inhalation can be harmful.

The other options do not accurately describe formaldehyde in its common state, which is why they do not fit as correct answers.