Answer:
0.00683 grams MgC₂O₄
Step-by-step explanation:
To find the mass of MgC₂O₄, you need to (1) convert atoms to moles (using Avogadro's Number), then (2) convert moles C to moles MgC₂O₄ (using mole-to-mole ratio), and then (3) convert moles MgC₂O₄ to grams (using molar mass). It is important to arrange the conversions in a way that allows for the cancellation of units. The final answer should have 3 sig figs like the given value.
Avogadro's Number:
6.022 x 10²³ atoms = 1 mole
1 MgC₂O₄ ----> 1 Mg + 2 C + 4 O
Atomic Mass (Mg): 24.305 g/mol
Atomic Mass (C): 12.011 g/mol
Atomic Mass (O): 15.999 g/mol
Molar Mass (MgC₂O₄): 24.305 g/mol + 2(12.011 g/mol) + 4(15.999 g/mol)
Molar Mass (MgC₂O₄): 112.323 g/mol
7.32 x 10¹⁹ atoms C 1 mole 1 mole MgC₂O₄
-------------------------------- x ------------------------------- x -------------------------- x
6.022 x 10²³ atoms 2 moles C
112.323 grams MgC₂O₄
------------------------------------- = 0.00683 grams MgC₂O₄
1 mole