How many moles of H2O are needed to react with 15.0g of CaO forming Ca (OH)2

CaO + H2O --> Ca (OH)2

Make sure the equation is balanced.

Convert 15.0 g CaO to mols. mol = grams/molar mass = ?

Now use the coefficients in the balanced equation to convert mols of what you have to mols of what you want.

To determine how many moles of H2O are needed to react with 15.0g of CaO, we will use the balanced chemical equation:

CaO + H2O -> Ca(OH)2

First, we need to find the molar mass of CaO and H2O:

The molar mass of CaO (calcium oxide) can be calculated by finding the atomic masses of calcium (Ca) and oxygen (O) from the periodic table and multiplying them by their respective subscripts in the chemical formula:

Molar mass of CaO = (1 x atomic mass of calcium) + (1 x atomic mass of oxygen)

The atomic masses are approximately:

- Atomic mass of calcium (Ca) = 40.08 g/mol
- Atomic mass of oxygen (O) = 16.00 g/mol

Molar mass of CaO = (1 x 40.08) + (1 x 16.00) = 56.08 g/mol

Next, we convert the given mass of CaO to moles using its molar mass:

Moles of CaO = Mass of CaO / Molar mass of CaO

Moles of CaO = 15.0 g / 56.08 g/mol ≈ 0.267 mol

According to the balanced equation, the ratio of CaO to H2O is 1:1. This means that for every 1 mole of CaO, we need 1 mole of H2O.

Therefore, the number of moles of H2O needed to react with 15.0g of CaO is also approximately 0.267 mol.