How to Calculate the Number of Formula Units in a Given Mass of Alumina (Al₂O₃)?
What is the question related to the data?
How many formula units are in 9.3 g of alumina (Al₂O₃)?
What are the steps to calculate this?
Answer:
5.5 × 10²² formula units Al₂O₃
In order to calculate the number of formula units in a given mass of alumina (Al₂O₃), you can follow these steps:
Step 1: Define the Given Mass
Given mass of Al₂O₃ is 9.3 g
Step 2: Define Conversions
Avogadro's Number: 6.022 × 10²³ formula units/mol
Molar Mass of Al: 26.98 g/mol
Molar Mass of O: 16.00 g/mol
Molar Mass of Al₂O₃: 2(26.98) + 3(16.00) = 101.96 g/mol
Step 3: Convert
9.3 g Al₂O₃ x (1 mol Al₂O₃ / 101.96 g Al₂O₃) x (6.022 × 10²³ formula units Al₂O₃ / 1 mol Al₂O₃) = 5.5 × 10²² formula units Al₂O₃
Step 4: Check
Given data has 2 significant figures, so the final answer is approximately 5.5 × 10²² formula units Al₂O₃