GK
GENERAL SCIENCE
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Question
[CLICK ON ANY CHOICE TO KNOW THE RIGHT ANSWER]
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Magnesium, tin and iron
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Calcium, magnesium and iron
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Magnesium, Calcium and tin
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Iron, tin and calcium
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Detailed explanation-1: -Hard water is water containing high amounts of mineral ions. The most common ions found in hard water are the metal cations calcium (Ca2+) and magnesium (Mg2+), though iron, aluminum, and manganese may also be found in certain areas.
Detailed explanation-2: -Hard water is water that has high mineral content (in contrast with “soft water"). Hard water is formed when water percolates through deposits of limestone, chalk or gypsum, which are largely made up of calcium and magnesium carbonates, bicarbonates and sulfates.
Detailed explanation-3: -Dissolved calcium and magnesium are the two most common minerals that make water “hard”. The degree of hardness becomes greater as the calcium and magnesium content increases.