The acid present in the atmosphere of Venus is:

The atmosphere of Venus is notably covered by thick, opaque clouds composed primarily of droplets of sulphuric acid. These clouds are responsible for the planet's characteristic yellowish-white appearance and its high reflectivity. While the bulk of Venus's atmosphere is carbon dioxide (96.5%), its upper cloud deck is dominated by concentrated sulphuric acid. Sulphuric acid is formed photochemically when sunlight triggers reactions between sulphur dioxide and water vapour in the upper atmosphere. Despite being further from the Sun than Mercury, Venus is the hottest planet in the solar system due to a runaway greenhouse effect caused by its dense carbon dioxide atmosphere.