To determine the amount of sulphuric acid needed for the production of 1000 kg of HCl, we first need to calculate the mass of HCl required.
Given:
- The reaction equation: 2NaCl + H2SO4 -> Na2SO4 + 2HCl
- The desired mass of HCl: 1000 kg
- The percentage composition of HCl in the final product: 42%
Step 1: Calculate the mass of HCl required
The mass of HCl required can be calculated using the formula:
Mass of HCl = (Percentage of HCl / 100) x Total mass
In this case, the percentage of HCl is given as 42% and the total mass is 1000 kg.
Mass of HCl = (42 / 100) x 1000 kg
Mass of HCl = 420 kg
Step 2: Calculate the mass of H2SO4 required
To find out the mass of sulphuric acid needed, we need to consider the stoichiometry of the reaction. From the balanced equation, we can see that 2 moles of HCl are produced from 1 mole of H2SO4.
To calculate the moles of HCl required, we need to convert the mass of HCl to moles using its molar mass.
Molar mass of HCl = 1 g/mol (1 hydrogen atom + 1 chlorine atom)
Moles of HCl = Mass of HCl / Molar mass of HCl
Moles of HCl = 420 kg / (1 g/mol) = 420,000 moles
Since the stoichiometry ratio is 1:2 for H2SO4:HCl, the moles of H2SO4 required will be half of the moles of HCl.
Moles of H2SO4 = Moles of HCl / 2
Moles of H2SO4 = 420,000 moles / 2 = 210,000 moles
Step 3: Calculate the mass of H2SO4 required
To find the mass of sulphuric acid, we need to multiply the moles of H2SO4 by its molar mass.
Molar mass of H2SO4 = 98 g/mol (2 hydrogen atoms + 1 sulfur atom + 4 oxygen atoms)
Mass of H2SO4 = Moles of H2SO4 x Molar mass of H2SO4
Mass of H2SO4 = 210,000 moles * 98 g/mol
Mass of H2SO4 = 20,580,000 g or 20,580 kg
Therefore, approximately 20,580 kg of sulphuric acid containing 90% H2SO4 by weight is needed for the production of 1000 kg of HCl containing 42% HCl by weight in this reaction.