Determine the number of moles of
a) N atoms in 42.5g of Mg(NO3)2
b) N atoms in a sample of C7H5(NO2)3 that has the same number of O atoms as 12.6g C6H12O6
Why are you posting multiple questions under different names?
You can figure the number of moles of molecules from the mol mass. Then, multiply by the number of atoms per mol mass.
i don't get what u mean
What is the molar mass of Mg(NO3)2? How many mols of Mg(NO3)2 are there in 42.5 g? How many mols N are in 1 mol Mg(NO3)2?
To determine the number of moles of N atoms in the given compounds, we need to follow a step-by-step process. First, we need to find the molar mass of each compound, then calculate the number of moles of each compound. Finally, we can determine the number of moles of N atoms based on the stoichiometry of each compound.
a) To find the number of moles of N atoms in 42.5g of Mg(NO3)2:
1. Calculate the molar mass of Mg(NO3)2:
- The molar mass of Mg = 24.31 g/mol (from the periodic table)
- The molar mass of N = 14.01 g/mol (from the periodic table)
- The molar mass of O = 16.00 g/mol (from the periodic table)
- Since there are two NO3 groups, the molar mass of NO3 is (14.01 + 3 * 16.00) g/mol = 62.01 g/mol.
- Therefore, the molar mass of Mg(NO3)2 is (24.31 + 2 * 62.01) g/mol = 148.33 g/mol.
2. Calculate the number of moles of Mg(NO3)2:
- Number of moles = mass / molar mass
- Number of moles = 42.5 g / 148.33 g/mol ≈ 0.2866 mol
3. Calculate the number of moles of N atoms:
- In one molecule of Mg(NO3)2, there are two N atoms.
- Therefore, the number of moles of N atoms in 42.5g of Mg(NO3)2 is 0.2866 mol * 2 = 0.5732 mol.
b) To find the number of moles of N atoms in a sample of C7H5(NO2)3 that has the same number of O atoms as 12.6g of C6H12O6:
1. Calculate the molar mass of C7H5(NO2)3:
- The molar mass of C = 12.01 g/mol (from the periodic table)
- The molar mass of H = 1.008 g/mol (from the periodic table)
- The molar mass of N = 14.01 g/mol (from the periodic table)
- The molar mass of O = 16.00 g/mol (from the periodic table)
- Considering all the atoms, the molar mass of C7H5(NO2)3 is (7 * 12.01) + (5 * 1.008) + (3 * (14.01 + 2 * 16.00)) g/mol ≈ 227.15 g/mol.
2. Calculate the number of moles of C7H5(NO2)3 with the same number of O atoms as 12.6g of C6H12O6:
- Calculate the molar mass of C6H12O6:
- (6 * 12.01) + (12 * 1.008) + (6 * 16.00) g/mol ≈ 180.16 g/mol.
- Calculate the number of moles using the molar mass and the given mass:
- Number of moles = mass / molar mass
- Number of moles = 12.6 g / 180.16 g/mol ≈ 0.0699 mol.
3. Calculate the number of moles of N atoms:
- In one molecule of C7H5(NO2)3, there are three N atoms.
- Therefore, the number of moles of N atoms in the sample with the same number of O atoms as 12.6g of C6H12O6 is 0.0699 mol * 3 = 0.2097 mol.
So, the number of moles of N atoms in:
a) 42.5g of Mg(NO3)2 is approximately 0.5732 mol.
b) A sample of C7H5(NO2)3 with the same number of O atoms as 12.6g of C6H12O6 is approximately 0.2097 mol.