What is the specific gravity (SG) of sulfur dioxide?

The specific gravity (SG) of a substance is defined as the ratio of the density of that substance to the density of a reference substance, usually water for liquids and gases at a specified temperature and pressure. For gases, specific gravity can help determine how heavy a gas is compared to air, which has a specific gravity of about 1.

In the case of sulfur dioxide (SO₂), its specific gravity is approximately 2.263. This means that sulfur dioxide is more than twice as heavy as air. This property is particularly relevant in various applications, including industrial processes and environmental monitoring, as it helps predict how the gas will behave in different atmospheric conditions.

The other options do not correspond to the known specific gravity of sulfur dioxide based on standard measurements. Specifically, a specific gravity of 1.263 would imply a gas lighter than air, while higher values like 3.263 and 4.263 reflect densities that are much heavier than sulfur dioxide actually is in relation to air. Understanding the specific gravity of sulfur dioxide can be critical when assessing its potential risks and behavior in various environments.