MARTYN F. CHILLMAID / SCIENCE PHOTO LIBRARY MARTYN F. CHILLMAID / SCIENCE PHOTO LIBRARY
Iron reacting with hydrochloric acid. Image 1 of 4. Iron (Fe) reacts with hydrochloric acid (HCl) to form iron (II) chloride (FeCl2). Bubbles of hydrogen gas (H2) are released during the reaction. This reaction is part of a demonstration showing the differences between a chemical and a physical change. A mixture of iron and sulphur (a physical change) has different properties from iron sulphide, the compound formed when they react together (a chemical change). This can be demonstrated by their reactivity with hydrochloric acid. Images A500/597, A500/598 and A500/599 respectively show sulphur, an iron/sulphur mixture and iron sulphide in hydrochloric acid.
Model release not required. Property release not required.