I assume you mean that you know what molecule it is, and how many grams of the substance you have, and want to know how many moles of the molecule you have.
1. Count how many atoms of each chemical element are present in the molecule.
2. Use a list of atom weights to find out the atom weight of each of the present atoms, i.e. the mole weight for every atom.
3. Add together the mole weight of the atoms in the molecule. This is the molecule weight.
4. Divide the weight of the substance you have with the molecule weight, and you will get the number of moles.
Example: I have 500.0 g of ethanol. How many moles is that?
1. The chemical formula of ethanol is C2H5OH, so every molecule consists of two carbon atoms, six hydrogen atoms and one oxygen atom.
2. I use a book to look up the atom weights, and find out that the following:
Carbon weighs 12.01 g/mole
Hydrogen weighs 1.008 g/mole
Oxygen weighs 16.00 g/mole
3. (2 * 12.01) + (6 * 1.008) + (1 * 16.00) = 46.068
4. 500.0 g / 46.068 g/mole = 10.85 moles
To find the number of particles in a compound when given the mass, first calculate the number of moles using the provided mass and the molar mass of the compound. Then, use Avogadro's number (6.022 x 10^23 particles/mol) to convert the moles to the number of particles in the compound.
For this you need the atomic (molecular) mass of C6H5OH. Take the number of grams and divide it by the atomic mass. Multiply by one mole for units to cancel. C6H5OH=94.1 grams25.5 grams C6H5OH / (94.1 grams) = .271 moles C6H5OH
No, you do not need to know the atomic weight to calculate molarity. Molarity is calculated by dividing the moles of solute by the volume of solution in liters. Knowing the atomic weight can help determine the number of moles in a given mass of solute, but it is not required to calculate molarity.
To calculate the volume of a compound when given its molecular weight and weight, you need to first convert the weight to moles using the molecular weight. Then, you can use the density of the compound to find the volume by dividing the weight in moles by the density. The formula is volume = weight (in moles) / density.
To find the number of moles of Na2SO4 in 25.0 g of the compound, you need to convert the mass to moles. First, determine the molar mass of Na2SO4, then divide the given mass by the molar mass to obtain the number of moles.
To find the number of particles in a compound when given the mass, first calculate the number of moles using the provided mass and the molar mass of the compound. Then, use Avogadro's number (6.022 x 10^23 particles/mol) to convert the moles to the number of particles in the compound.
To find the number of moles of MgCl2 in 317 g of the compound, first calculate the molar mass of MgCl2 (95.21 g/mol). Then, divide the given mass by the molar mass to get the number of moles: 317 g / 95.21 g/mol = 3.33 moles of MgCl2.
To determine the number of moles of Fe2O3 in 217g of the compound, you first need to calculate the molar mass of Fe2O3, which is 159.69 g/mol. Then, divide the given mass (217g) by the molar mass to find the moles. Moles = 217g / 159.69 g/mol = 1.36 moles of Fe2O3.
To find the number of moles, first calculate the molar mass of sodium nitrate (NaNO3), which is 85 grams/mol. Then, divide the given mass (2.85 grams) by the molar mass to obtain the number of moles present, which is approximately 0.0335 moles.
To find the number of moles of MgS2O3 in 211 g of the compound, you need to first calculate the molar mass of MgS2O3. This is 120.37 g/mol. Then, divide the given mass by the molar mass to get the number of moles. In this case, 211 g / 120.37 g/mol = 1.75 moles of MgS2O3.
To find the number of moles in 215 g of MgS2O3, you first need to calculate the molar mass of the compound. The molar mass of MgS2O3 is 120.3 g/mol. Next, divide the given mass (215 g) by the molar mass to find the number of moles. Therefore, 215 g of MgS2O3 is equal to 1.79 moles.
To find the molar mass of the nonelectrolyte compound, we need to use the formula: Molar mass (mass of compound / moles of compound) First, we need to find the moles of the compound by using the formula: moles mass / molar mass Given that the mass of the compound is 4.305 g and it is dissolved in 105 g of water, we can calculate the moles of the compound. Next, we can find the molar mass of the compound by rearranging the formula: Molar mass mass / moles By plugging in the values, we can calculate the molar mass of the nonelectrolyte compound.
To find the number of moles from molar mass, divide the mass of the compound by its molar mass. The formula is: Moles = Mass (g) / Molar Mass (g/mol). This will give you the number of moles of the unknown compound.
To calculate the number of moles in a sample of Al2O3, we need to use the molar mass of Al2O3, which is 101.96 g/mol. Number of moles = Mass / Molar mass = 6.80g / 101.96 g/mol ≈ 0.067 moles. Therefore, there are approximately 0.067 moles of Al2O3 in 6.80g of the compound.
To determine the number of moles in a given sample, you can use the formula: moles mass of sample (in grams) / molar mass of the substance. This formula helps you calculate the amount of substance in terms of moles based on its mass and molar mass.
To find the number of moles of sodium sulfate in 0.1000g of the compound, you first need to determine the molar mass of Na2SO4. Then, divide the given mass by the molar mass to get the moles.
A mole is a defined number of atoms/molecules of an element/compound. Therefore, the number of moles of NaCHO3 will depend on the mass of NaCHO3 that you have. To calculate the number of moles in a known sample, divide the mass of the sample (in grams) by the molecular weight.