Water containing high concentrations of calcium, magnesium, and iron (II) ions is referred to as what?

Water that contains high concentrations of calcium, magnesium, and iron (II) ions is referred to as hard water. This type of water has a significant amount of dissolved minerals, primarily calcium and magnesium, which contribute to its "hardness." When water is described as hard, it typically means that these minerals can lead to scaling in pipes and appliances, and they can also affect the ability of soap to lather, resulting in the need for more soap to achieve the desired effect.

In contrast, soft water has low concentrations of these minerals and is often treated to remove hardness, making it more suitable for washing and cooking. Distilled water is purified water that has been boiled to remove impurities, including minerals, while pure water generally refers to water that is free from contaminants but does not specifically indicate the presence or absence of hardness minerals.