How do I prepare 3% H2SO4 from concentrated sulphuric acid (98% with density 1.84g/ml)?
To prepare a 3% H2SO4 solution from concentrated sulphuric acid (98%), you can follow these steps:
Step 1: Calculate the amount of concentrated sulphuric acid needed.
- The desired concentration is 3% by volume. This means that for every 100 ml of the solution, 3 ml should be H2SO4.
- The concentrated sulphuric acid is 98% by weight and has a density of 1.84g/ml.
- Since density = mass/volume, we can calculate the mass of concentrated sulphuric acid needed for 3 ml of H2SO4.
Mass of concentrated H2SO4 = (Volume of H2SO4 needed * Density of concentrated H2SO4)
= (3 ml * 1.84 g/ml)
= 5.52 g
Step 2: Calculate the amount of water needed.
- To prepare the final solution, water is required. The total volume required is 100 ml, whereas we have already added 3 ml of H2SO4.
- So, the remaining volume of the solution is 100 ml - 3 ml = 97 ml, which should be water.
Step 3: Mix the concentrated sulphuric acid and water.
- Carefully measure out the 5.52 g of concentrated H2SO4 using a measuring cylinder.
- Take a container (such as a beaker or flask) and add the measured concentrated H2SO4 into it.
- Slowly and carefully add the required amount of water (97 ml) to the concentrated H2SO4 in the container.
- Mix the solution thoroughly until the H2SO4 dissolves completely in water. Make sure to take appropriate precautions such as wearing gloves, goggles, and working in a well-ventilated area, as concentrated sulphuric acid is highly corrosive and should be handled with care.
You have now prepared a 3% H2SO4 solution from concentrated sulphuric acid.