Scale is formed from the combination of which?

Scale is formed from the combination of which?

• A. monovalent metallic ions with carbonates or sulfates
• B. monovalent metallic cations and minerals dissolved in water
• C. divalent metallic ions with carbonates or sulfates
• D. divalent metallic cations and minerals dissolved in water

Answer: (D)

Scale forms when minerals dissolved in water come out of solution and deposit on surfaces. The key players are divalent metal ions, such as calcium and magnesium, which readily combine with minerals dissolved in the water—especially carbonates and sulfates—to precipitate as solid deposits. That broad description fits the common causes of scale, like calcium carbonate or calcium sulfate, and even other mineral combinations involving these divalent cations. Monovalent ions (like sodium or potassium) don’t typically form the hard mineral deposits we call scale, so the option that centers on divalent cations with dissolved minerals best describes the phenomenon.

Scale forms when minerals dissolved in water come out of solution and deposit on surfaces. The key players are divalent metal ions, such as calcium and magnesium, which readily combine with minerals dissolved in the water—especially carbonates and sulfates—to precipitate as solid deposits. That broad description fits the common causes of scale, like calcium carbonate or calcium sulfate, and even other mineral combinations involving these divalent cations. Monovalent ions (like sodium or potassium) don’t typically form the hard mineral deposits we call scale, so the option that centers on divalent cations with dissolved minerals best describes the phenomenon.