Calculate the number of moles in each substance
a. 1.68 g of magnesium ions
b. 69.6 g of sodium hypochlorite
c. 4.27 * 10^24 molecules of carbon monoxide
a and b. mols = grams/molar mass = ?
c. There are 6.02 x 10^23 molecules in a mole of molecules.
Post your work if you get stuck.
To calculate the number of moles in each substance, you need to use the formula:
Number of moles = Mass / Molar mass
a. 1.68 g of magnesium ions:
To find the molar mass of magnesium ions (Mg²⁺), you need to know the atomic mass of magnesium (24.31 g/mol) and the charge (2+). So the molar mass of magnesium ions is 24.31 g/mol. Now you can calculate the number of moles:
Number of moles = 1.68 g / 24.31 g/mol
b. 69.6 g of sodium hypochlorite:
Sodium hypochlorite (NaClO) consists of sodium, chlorine, and oxygen atoms. To calculate the molar mass, you need to find the atomic masses of each element. The atomic masses are: sodium (22.99 g/mol), chlorine (35.45 g/mol), and oxygen (16.00 g/mol). The molar mass of NaClO is the sum of the atomic masses: 22.99 + 35.45 + 16.00 = 74.44 g/mol. Now you can calculate the number of moles:
Number of moles = 69.6 g / 74.44 g/mol
c. 4.27 * 10^24 molecules of carbon monoxide:
To calculate the number of moles, you need to know the Avogadro's number (6.022 × 10^23). Since you have the number of molecules (4.27 × 10^24), you can use the following formula:
Number of moles = Number of molecules / Avogadro's number
Number of moles = 4.27 * 10^24 molecules / 6.022 × 10^23 molecules/mol
To calculate the number of moles in a substance, we need to use the formula:
Number of moles = Mass (in grams) / Molecular weight (in grams/mol)
Let's calculate the number of moles for each substance.
a. 1.68 g of magnesium ions:
To find the molecular weight of magnesium ions, we need to know the charge on the ion. Assuming we have a magnesium ion with a +2 charge (Mg2+), the atomic mass of magnesium (Mg) is 24.31 g/mol.
Number of moles = 1.68 g / 24.31 g/mol = 0.069 moles
Therefore, 1.68 g of magnesium ions is equal to approximately 0.069 moles.
b. 69.6 g of sodium hypochlorite:
The molecular formula of sodium hypochlorite is NaOCl. To calculate the molecular weight, we need to add up the atomic masses of each element: sodium (Na), oxygen (O), and chlorine (Cl).
Atomic mass of sodium (Na) = 22.99 g/mol
Atomic mass of oxygen (O) = 16.00 g/mol
Atomic mass of chlorine (Cl) = 35.45 g/mol
Molecular weight of NaOCl = (22.99 g/mol) + (16.00 g/mol) + (35.45 g/mol) = 74.44 g/mol
Number of moles = 69.6 g / 74.44 g/mol = 0.935 moles
Therefore, 69.6 g of sodium hypochlorite is equal to approximately 0.935 moles.
c. 4.27 * 10^24 molecules of carbon monoxide:
To calculate the number of moles from the given number of molecules, we need to know Avogadro's number, which is 6.022 × 10^23 molecules/mol.
Number of moles = (4.27 * 10^24 molecules) / (6.022 × 10^23 molecules/mol)
≈ 7.09 moles
Therefore, 4.27 * 10^24 molecules of carbon monoxide is equal to approximately 7.09 moles.