Respuesta :
Answer:
10.3 g Al
Explanation:
To find the excess mass of Al, you need to (1) convert grams Iā to moles Iā Ā (via molar mass), then (2) convert moles Iā to moles AlIā (via mole-to-mole ratio from equation coefficients), then (3) convert moles AlIā to grams AlIā (via molar mass). Now that you have the actual amount of AlIā produced, you need to (4) convert grams AlIā to moles AlIā (via molar mass), then (5) convert moles AlIā to moles Al (via mole-to-mole ratio from equation coefficients), and then (6) convert moles Al to grams Al (via molar mass). Now that you know the amount of Al actually needed to produce the product, you need to (7) find the excess mass of Al.
Molar Mass (Al): 26.982 g/mol
Molar Mass (Iā): 2(126.90 g/mol)
Molar Mass (Iā): 253.8 g/mol
Molar Mass (AlIā): 26.982 g/mol + 3(126.90 g/mol)
Molar Mass (AlIā): 407.682 g/mol
2 Al(s) + 3 Iā(g) -------> 2 AlIā(g)
Ā 113 g Iā Ā Ā Ā Ā Ā 1 mole Ā Ā Ā Ā Ā Ā 2 moles AlIā Ā Ā Ā Ā Ā 407.682 g
------------- Ā x Ā ---------------- Ā x Ā ---------------------- Ā x Ā ------------------- Ā = Ā 121 g AlIā
Ā Ā Ā Ā Ā Ā Ā Ā Ā Ā Ā Ā 253.8 g Ā Ā Ā Ā Ā Ā 3 moles Iā Ā Ā Ā Ā Ā Ā Ā 1 mole
121 g AlIā Ā Ā Ā Ā Ā 1 mole Ā Ā Ā Ā Ā Ā Ā Ā 2 moles Al Ā Ā Ā Ā Ā 26.982 g
--------------- Ā x Ā ------------------ Ā x Ā --------------------- Ā x Ā ----------------- Ā = Ā 8.01 g Al
Ā Ā Ā Ā Ā Ā Ā Ā Ā Ā Ā Ā 407.682 g Ā Ā Ā Ā Ā 2 moles AlIā Ā Ā Ā Ā Ā 1 mole
Starting Amount - Mass Needed = Excess
18.3 g Al - 8.01 g Al = 10.3 g Al