Calculate mole fraction of HCl in a solution containing 24.8% HCl by mass
24.8% HCl w/w means
24.8 g HCl/(100 g solution)
100 g solution = 24.8g HCl + 75.2g H2O.
mols HCl = grams/molar mass = ?
mols H2O = grams/molar mass = ?
total mols = ?
XHCl = mols HCl/total mols.
To calculate the mole fraction of HCl in a solution, we need to first convert the mass percentage of HCl into a molar concentration.
Step 1: Convert mass percentage to mass of HCl
In a solution containing 24.8% HCl by mass, it means that 24.8 grams of HCl is present in every 100 grams of the solution. So, if we have a certain mass of the solution, we can calculate the mass of HCl using this proportion.
For example, if we have 200 grams of the solution:
Mass of HCl = (24.8/100) * 200 grams
= 49.6 grams
Step 2: Convert mass of HCl to moles
To convert the mass of HCl to moles, we need to know its molar mass. The molar mass of HCl is 36.46 grams/mole.
Number of moles of HCl = Mass of HCl / Molar mass of HCl
= 49.6 grams / 36.46 grams/mole
≈ 1.36 moles
Step 3: Calculate mole fraction of HCl
The mole fraction of a component in a solution is defined as the ratio of the moles of that component to the total moles of all components in the solution.
Mole fraction of HCl = Moles of HCl / Total moles in the solution
Since we only have HCl in this case, the mole fraction of HCl will be 1.
Mole fraction of HCl = 1
So, the mole fraction of HCl in a solution containing 24.8% HCl by mass is 1.