What is the molar mass of Ca(OH)_2?

• A. 74.10 g/mol
• B. 90.08 g/mol
• C. 56.08 g/mol
• D. 40.08 g/mol

Answer: (A)

Verified step by step guidance

1. Identify the chemical formula of the compound: Ca(OH)\_2, which consists of 1 calcium (Ca) atom, 2 oxygen (O) atoms, and 2 hydrogen (H) atoms.
2. Find the atomic masses of each element from the periodic table: calcium (Ca) ≈ 40.08 g/mol, oxygen (O) ≈ 16.00 g/mol, and hydrogen (H) ≈ 1.008 g/mol.
3. Calculate the total mass contributed by each element by multiplying the atomic mass by the number of atoms in the formula: for Ca, multiply by 1; for O, multiply by 2; for H, multiply by 2.
4. Add all the contributions together to find the molar mass of Ca(OH)\_2 using the formula: \(\text{Molar mass} = (1 \times M_{Ca}) + (2 \times M_{O}) + (2 \times M_{H})\).
5. Sum the values obtained to get the total molar mass of Ca(OH)\_2 in grams per mole.