Based on the balanced equation
4Na + O2 → 2Na2O
calculate the number of Na2O formula units formed when 60 Na atoms and 10 O2 molecules react?
Thanks.
You are limited to 20 O, and 30Na2, so the overall limit is 20 O in 2Na2O, so the total Na2O has to be 20 total max.
Formula compound
To calculate the number of Na2O formula units formed, we need to first determine the limiting reactant. The limiting reactant is the reactant that is completely consumed and determines the maximum amount of product that can be formed.
Step 1: Convert the given quantities to moles
- 60 Na atoms: Use Avogadro's number to convert atoms to moles. 1 mole of Na contains 6.022 x 10^23 atoms. Therefore, 60 Na atoms is equal to 60/6.022 x 10^23 = 9.958 x 10^-23 moles of Na.
- 10 O2 molecules: 1 mole of O2 contains 6.022 x 10^23 molecules. Therefore, 10 O2 molecules is equal to 10/6.022 x 10^23 = 1.659 x 10^-23 moles of O2.
Step 2: Determine the molar ratio between Na and Na2O
From the balanced equation, we can see that the ratio between Na and Na2O is 4:2, which can be simplified to 2:1. This means that for every 2 moles of Na, 1 mole of Na2O is formed.
Step 3: Determine the limiting reactant
To determine the limiting reactant, we compare the ratios of moles of each reactant to the stoichiometric ratio. For Na, the moles available are 9.958 x 10^-23, and for O2, the moles available are 1.659 x 10^-23.
Since the stoichiometric ratio is 2:1 (2 moles of Na to 1 mole of Na2O), we need to calculate how many moles of Na2O can be formed from both reactants.
For Na: 9.958 x 10^-23 moles of Na * (1 mole Na2O / 2 moles Na) = 4.979 x 10^-23 moles of Na2O can be formed.
For O2: 1.659 x 10^-23 moles of O2 * (1 mole Na2O / 1 mole O2) = 1.659 x 10^-23 moles of Na2O can be formed.
Therefore, the limiting reactant is Na, as it produces less moles of Na2O compared to O2.
Step 4: Calculate the number of Na2O formula units formed
Since we have determined the limiting reactant, we now use its amount to calculate the number of Na2O formula units formed.
Using the 4.979 x 10^-23 moles of Na2O calculated in Step 3, we can convert it to the number of formula units. 1 mole of any substance contains 6.022 x 10^23 formula units.
Therefore, 4.979 x 10^-23 moles of Na2O * (6.022 x 10^23 formula units Na2O / 1 mole Na2O) = 2.999 x 10 formula units of Na2O.
So, when 60 Na atoms and 10 O2 molecules react, the number of Na2O formula units formed is approximately 3.0 x 10^23.