Respuesta :
Answer:
5.00 atoms containing 8.3 *10^-24 moles this is 4.3 * 10^-22 grams
1020 atoms containing 1.69*10^-21 moles this is 8.8 *10^-20 grams
Explanation:
Step 1: Data given
Sample 1: contains 5.00 chromium atoms
Number of Avogadro = 6.022 * 10^23 / mol
Molar mass of chromium = 52 g/mol
Step 2: Calculate number of moles in 5.00 chromium atoms
Moles = atoms / number of Avogadro
Moles = 5.00 / 6.022 *10^23
Moles = 8.3 *10^-24 moles
Step 3: Calculate mass of 5.00 moles chromium atoms
Mass = moles *molar mass
Mass = 8.3 *10^-24 moles * 52 g/mol
Mass =4.3 * 10^-22 grams
Step 1: Data given
Sample 1: contains 1020 chromium atoms
Number of Avogadro = 6.022 * 10^23 / mol
Step 2: Calculate number of moles in 1020 chromium atoms
Moles = atoms / number of Avogadro
Moles = 1020 / 6.022 *10^23
Moles = 1.69*10^-21 moles
Step 3: Calculate mass of 1020 moles chromium atoms
Mass = moles *molar mass
Mass = 1.69*10^-21 moles * 52 g/mol
Mass = 8.8 *10^-20 grams
