Final answer:
The clouds in Venus's atmosphere primarily consist of sulfuric acid, a result of the combination of sulfur dioxide and water in the planet's dry and carbon dioxide-dense atmosphere.
Step-by-step explanation:
The clouds in the atmosphere of Venus consist primarily of sulfuric acid (H₂SO₄). This is due to the chemical combination of sulfur dioxide (SO₂) and water (H₂O) occurring in the Venusian atmosphere.
Unlike Earth where sulfur dioxide is quickly washed out by rain, Venus's dry atmosphere allows sulfuric acid to stabilize within its thick cloud layer, located between 30 and 60 kilometers above the surface. Furthermore, Venus's atmosphere is composed mainly of carbon dioxide (CO₂), which accounts for 96%, with the second most common gas being nitrogen. However, the sulfuric acid clouds are one of the defining features of Venus's upper troposphere.