In this post we will discuss how to prepare 1M and 1N sulfuric acid solutions, it's difference and standarization. As we know that sulfuric acid is highly corrosive, follow the following steps very carefully. We have to always add acid to water, never try to add water to the acid beacuse it may cause dangerous reactions. Analyst should wear proper safety equipment (goggles, gloves, lab coat) and work in a well-ventilated area or fume hood.
Before preparing 1M and 1N solution we have to know what is molarity and normality.
Molarity: It is the number of moles of solute dissolved in one litre of solution. The symbol of Molarity is "M". 1M (1 molar) solution: Contains 1 mole of sulfuric acid (H₂SO₄) per liter of solution.
Normality: It is the number of gram equivalent weight of solute present in one litre of solution. It is mostly denoted by symbol "N". 1N (1 normal) solution: Contains 1 equivalent of reactive ions per liter.
Equivalent Weight is calulated as molecular weight or molar mass divided by valency (ɳ) or acidity or Basicity. Valency depends on the what type of reaction occurs like acid-base, redox.
For Acid: (ɳ)=Basicity: It is the number of replaceable hydrogen ions (H+).
For Base: (ɳ)=Acidity: It is the number of replaceable hydroxyl ion (OH-).
For Salts: (ɳ)= It is the total charge of either the cation or anion.
For redox reaction: (ɳ)= It is the number of electrons lost or gained per molecule.
Calculation for 1 M Sulphuric Acid Solution
So first of all we have calculate the molarity of 97% Sulphuric acid by using given formula:
Procedure to prepare 1M Sulphuric Acid of 1000 ml
Calculation for 1 N Sulphuric Acid Solution
As we know that Sulphuric Acid has two replaceable "hydrogen ion". So the basicity H2SO4 is "2".
Now calculate the molarity of sulphuric acid as calculate above for 1 M solution.
The relaation between both is as: Normality= Molarity X Basicity. The Normality of 97% pure sulphuric acid is 18.2 M and basicity is 2 then
Normality= 18.2 x 2=36.4N
Preparation steps for 1 N Sulphuric Acid.
Follow the same steps as above, (i.e. during preparation of 1 M sulphuric acid) but use 27.47 mL of concentrated sulfuric instead of 54.95 mL.
Standarization of 1M sulphuric acid
Standarization is performed to determine its actual concentration by using a primary standard solution using titration method. Most common primary standard used for its determination is sodium carbonate (Na2CO3).
Material Required:
- Sulphuric Acid of Approx. Concentration
- Sodium Carbonate (as primary standard)
- Methyl Orange Indicator
- Distilled water
- Appratus like Burette, Conical flask, volumetric flask, mesuring cylinder, pipette.
Procedure for standarization:
Step 1: Prepration of primary standard solution
i. Accurately weigh the anhydrous sodium carbonate 1.5g on watch glass with the help of weighing balance.
ii. Dissolve the sodium carbonate properly in beaker containing about 70 ml distilled water by continuous stirring. Also wash the watch glass 2 or 3 times in beaker with the help of washing bottle.
iii. After that transfer the solution in volumetric flask of 250 ml using funnel. Rinse the beaker with distilled water and collect washing in the V.F.
iv. Makeup the volume up to mark by adding distilled water. Now sodium carbonate solutin is prepared.
Step 2: Titration with Sulhuric Acid
i. Rinse the burette with sulphuric acid. Fill the sulphuric acid in the burette up to mark.
ii. Transfer 25 ml of sodium carbonate solution by pipetting into a conical flask.
iii. Add 2 or 3 drops of methyl orange indicator in the conical flask containing solution. The color of solution appears yellow.
iv. Record the intial reading. Titrate the sodium carbonate with sulphuric acid drop by drop until the color of solution change from yellow to orange and then permanent light pink.
v. Record the final reading ofburette. Measure the volume of sulphuric acid used. Also perform blank titation.
Reaction:
Factor calculation:
Safety notes
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