How to Calculate the Mass of 3.5 Moles of H2O in Grams?

To calculate the mass in grams of 3.5 moles of H2O, we need to know the molar mass of water (H2O). Each water molecule (H2O) consists of 2 hydrogen atoms and 1 oxygen atom. The molar mass of hydrogen (H) is approximately 1 gram/mol and the molar mass of oxygen (O) is about 16 grams/mol. Therefore, the molar mass of water (H2O) would be:

Molar Mass of H2O = 2(1 g/mol) + 1(16 g/mol) = 18 g/mol

Now, to find the mass in grams of 3.5 moles of H2O, we can use the formula:

Mass (g) = Number of Moles x Molar Mass

Substitute the values into the formula:

Mass (g) = 3.5 moles x 18 g/mol = 63 grams

Therefore, the mass in grams of 3.5 moles of H2O is 63 grams. This calculation is done by multiplying the number of moles (3.5) by the molar mass of water (H2O), which is 18 grams/mole.

Understanding the Calculation

Moles to Grams Conversion: When converting moles to grams, you need to know the molar mass of the compound. The molar mass is the mass in grams of one mole of a substance. By multiplying the number of moles by the molar mass, you can determine the mass of the substance in grams.

Molar Mass of Water (H2O): The molar mass of water (H2O) is 18 grams/mol. This is calculated by adding the molar masses of hydrogen (H) and oxygen (O) in the water molecule.

Calculation: In this case, to find the mass of 3.5 moles of water (H2O), you multiply the number of moles (3.5) by the molar mass of water (18 g/mol). This results in a mass of 63 grams.

Understanding how to calculate the mass of a substance from moles is essential in chemistry. It allows you to convert between different units of measurement and determine the quantity of a substance in a given sample.