Calcium Hydroxide has the formula Ca(OH)2. Which statement is correct?

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Multiple Choice

Calcium Hydroxide has the formula Ca(OH)2. Which statement is correct?

Chemical formulas show the balance and types of ions in a compound. Calcium hydroxide consists of one calcium ion with a 2+ charge and two hydroxide ions with a -1 charge, giving Ca2+ and 2 OH− to balance the charge. That 1:2 ratio is exactly what Ca(OH)2 represents, so Ca(OH)2 is the correct way to write calcium hydroxide. Other options correspond to different substances: CaO is calcium oxide (quicklime) with no hydroxide groups, NaOH is sodium hydroxide (a different base with sodium instead of calcium), and CaCO3 is calcium carbonate (which contains carbonate, not hydroxide). In practical terms, Ca(OH)2 is used in water treatment to adjust pH and in lime softening, aligning with its correct formula.

Chemical formulas show the balance and types of ions in a compound. Calcium hydroxide consists of one calcium ion with a 2+ charge and two hydroxide ions with a -1 charge, giving Ca2+ and 2 OH− to balance the charge. That 1:2 ratio is exactly what Ca(OH)2 represents, so Ca(OH)2 is the correct way to write calcium hydroxide. Other options correspond to different substances: CaO is calcium oxide (quicklime) with no hydroxide groups, NaOH is sodium hydroxide (a different base with sodium instead of calcium), and CaCO3 is calcium carbonate (which contains carbonate, not hydroxide). In practical terms, Ca(OH)2 is used in water treatment to adjust pH and in lime softening, aligning with its correct formula.

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