IGCSE Chemistry Practice Exam 2026 – Complete Study Resource

Barium sulfate is known for forming a white precipitate when barium ions react with sulfate ions in a solution. This characteristic is due to the low solubility of barium sulfate in water. When these ions combine, the solid precipitate that forms is typically observed as a bright white, chalky substance. This white coloration is a distinguishing feature that helps identify barium sulfate in chemical analyses. The other color options do not accurately represent the physical appearance of barium sulfate under normal conditions, as it does not exhibit green, yellow, or pink colors.