How many moles of water, H2O, are present in 75.0 g H2O?
4.2 mol
To determine the number of moles of water (H2O) present in 75.0 g, we need to use the molar mass of water.
The molar mass of water (H2O) is the sum of the atomic masses of hydrogen (H) and oxygen (O).
The atomic mass of hydrogen (H) is approximately 1.01 g/mol, and the atomic mass of oxygen (O) is about 16.00 g/mol.
To calculate the molar mass of water (H2O):
Molar mass of H2O = 2 * Molar mass of H + 1 * Molar mass of O
= 2 * 1.01 g/mol + 1 * 16.00 g/mol
≈ 18.02 g/mol
Now we can calculate the number of moles using the formula:
Number of moles = Mass / Molar mass
Number of moles of H2O = 75.0 g / 18.02 g/mol
≈ 4.16 moles
Therefore, there are approximately 4.16 moles of water (H2O) in 75.0 g of water.
To find the number of moles of water (H2O) present in 75.0 g H2O, you need to use the concept of molar mass and the formula:
Number of moles = Mass / Molar mass
First, you need to determine the molar mass of water (H2O).
The molar mass of H2O can be found by adding up the atomic masses of the atoms in one molecule of water.
The molar mass of hydrogen (H) is approximately 1 g/mol, and the molar mass of oxygen (O) is approximately 16 g/mol.
Now, calculate the molar mass of water:
Molar mass of H2O = (2 * Molar mass of hydrogen) + Molar mass of oxygen
= (2 * 1 g/mol) + 16 g/mol
= 18 g/mol
So, the molar mass of water is 18 g/mol.
Now, you can calculate the number moles of water present in 75.0 g H2O using the formula:
Number of moles = Mass / Molar mass
= 75.0 g / 18 g/mol
Calculating this, you get:
Number of moles = 4.167 mol
Therefore, there are approximately 4.167 moles of water (H2O) present in 75.0 g H2O.