How many atoms of Ag are in each of the following quantities?
1- 0.38 mole Ag2S?
2- 0.78 mole AgCl?
There are 6.022 x 10^23 molecules in a mole. Convert 0.38 mole Ag2S to molecules, then multiply by 2 since there are two Ag atoms per molecule Ag2S
To determine the number of atoms in a given quantity of a substance, you need to use Avogadro's number, which states that there are 6.022 × 10^23 atoms in one mole of any substance.
1. For Ag2S:
a. Calculate the molar mass of Ag2S:
- The atomic mass of Ag is 107.87 g/mol.
- The atomic mass of S is 32.07 g/mol.
- Multiply the atomic mass of Ag by 2 since there are two Ag atoms in Ag2S.
- Add the results of the individual atomic masses: 2 × 107.87 g/mol + 32.07 g/mol = 247.81 g/mol.
b. Calculate the number of moles:
- Use the given quantity, which is 0.38 mole Ag2S.
c. Calculate the number of atoms:
- Multiply the number of moles by Avogadro's number: 0.38 mole Ag2S × 6.022 × 10^23 atoms/mol = 2.29 × 10^23 atoms of Ag.
2. For AgCl:
a. Calculate the molar mass of AgCl:
- The atomic mass of Ag is 107.87 g/mol.
- The atomic mass of Cl is 35.45 g/mol.
- Add the results of the individual atomic masses: 107.87 g/mol + 35.45 g/mol = 143.32 g/mol.
b. Calculate the number of moles:
- Use the given quantity, which is 0.78 mole AgCl.
c. Calculate the number of atoms:
- Multiply the number of moles by Avogadro's number: 0.78 mole AgCl × 6.022 × 10^23 atoms/mol = 4.70 × 10^23 atoms of Ag.
Therefore, for each given quantity:
1- There are 2.29 × 10^23 atoms of Ag in 0.38 mole of Ag2S.
2- There are 4.70 × 10^23 atoms of Ag in 0.78 mole of AgCl.