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The molar mass of a compound is calculated by adding up the molar masses of each of the elements in the compound. The molar mass of an element is its atomic weight on the periodic table in g/mol.

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Step 1: Identify the Elements in the Compound 
Calcium hydroxide, Ca(OH)₂, is composed of calcium (Ca), oxygen (O), and hydrogen (H).

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Step 2: Find the Atomic Masses 
The atomic masses of these elements, usually found on the periodic table, are approximately: 
- Calcium (Ca): 40.08 g/mol 
- Oxygen (O): 16.00 g/mol 
- Hydrogen (H): 1.01 g/mol

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Step 3: Calculate the Molar Mass of the Compound 
The formula for calcium hydroxide shows that it contains one calcium atom, two oxygen atoms, and two hydrogen atoms. Therefore, to calculate the molar mass of calcium hydroxide, we add the molar mass of calcium to twice the molar mass of oxygen and twice the molar mass of hydrogen. 
 
- Molar mass of Ca: 1 x 40.08 g/mol = 40.08 g/mol 
- Molar mass of O: 2 x 16.00 g/mol = 32.00 g/mol 
- Molar mass of H: 2 x 1.01 g/mol = 2.02 g/mol

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Step 4: Add the Molar Masses Together 
The molar mass of calcium hydroxide is the sum of the molar masses of calcium, oxygen, and hydrogen. 
 
Molar mass of Ca(OH)₂ = 40.08 g/mol + 32.00 g/mol + 2.02 g/mol = 74.10 g/mol

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Therefore, the molar mass of calcium hydroxide, Ca(OH)₂, is 74.10 g/mol.

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