Deionized water is water with which of the following removed?

Deionized water is water that has had impurities and minerals, such as iron ions, removed through a process known as deionization. Iron can be naturally present in water sources or introduced through piping systems, and its removal is essential for producing deionized water. This is because iron can react with other chemicals and particles, leading to contamination and affecting the water's purity. Therefore, iron is one of the impurities removed during the deionization process to obtain high-quality, purified water.