The chemical formula for calcium hydroxide is: CaOH2 Calculate the molar mass of calcium hydroxide. Round your answer to 2 decimal .
The Correct Answer and Explanation is:
To calculate the molar mass of calcium hydroxide (Ca(OH)2), we need to find the atomic masses of each element in the formula and then sum them up, taking into account the number of atoms of each element.
Step-by-step calculation:
- Atomic Mass of Calcium (Ca):
The atomic mass of calcium (Ca) is 40.08 g/mol. - Atomic Mass of Oxygen (O):
The atomic mass of oxygen (O) is 16.00 g/mol. - Atomic Mass of Hydrogen (H):
The atomic mass of hydrogen (H) is 1.008 g/mol.
Now, let’s break down the molar mass calculation for Ca(OH)2:
- Calcium (Ca): 1 atom of calcium, so the contribution to the molar mass is: 1×40.08=40.08 g/mol1 \times 40.08 = 40.08 \, \text{g/mol}1×40.08=40.08g/mol
- Oxygen (O): 2 atoms of oxygen, so the contribution is: 2×16.00=32.00 g/mol2 \times 16.00 = 32.00 \, \text{g/mol}2×16.00=32.00g/mol
- Hydrogen (H): 2 atoms of hydrogen, so the contribution is: 2×1.008=2.016 g/mol2 \times 1.008 = 2.016 \, \text{g/mol}2×1.008=2.016g/mol
Total Molar Mass:
Now, sum up the contributions from each element:40.08+32.00+2.016=74.096 g/mol40.08 + 32.00 + 2.016 = 74.096 \, \text{g/mol}40.08+32.00+2.016=74.096g/mol
Rounding to two decimal places, the molar mass of calcium hydroxide (Ca(OH)2) is 74.10 g/mol.
Explanation:
The molar mass of a compound is the sum of the atomic masses of all the atoms in the formula, multiplied by their respective quantities. In this case, calcium hydroxide contains one calcium atom, two oxygen atoms, and two hydrogen atoms. By multiplying each element’s atomic mass by the number of atoms of that element in the formula and adding them together, we get the total molar mass of the compound, which is crucial for stoichiometric calculations in chemistry.
