Describe how you would prepare 0.5N sulphuric acid in 500mls specific gravity 1.84,percent purity 98
The wording is confusing. I'm assuming you want to prepare 500 ml of 0.5 N H2SO4 and you're starting with H2SO4 of specific gravity 1.84 g/mL and 98% purity.
What's the normality of the H2SO4, That's
1.84 g/mL x 1000 mL x 0.98 x (1/49) = ? N.= approx 36 N but you need to use a more accurate number.
Then mL1 x N1 = mL2 x N2 or
500mL x 0.5N = mL2 x 36N and solve for the mL2.
Then pipet mL2 from the pure 98% H2SO4 into a 500 mL flask THAT ALREADY CONTAINS SOME H2O (say 250 mL or so) and fill to the mark. Shake and stopper.
To prepare 0.5N sulfuric acid solution in 500 ml, you need to know the molar concentration of the solution and the specific gravity of the concentrated sulfuric acid. Here's how you can calculate it:
Step 1: Determine the molar concentration of the solution.
The normality (N) of a solution is a measure of its concentration in terms of chemical equivalents per liter. To calculate the molarity (M) from normality (N) for sulfuric acid, you need to consider that sulfuric acid is a diprotic acid with two replaceable hydrogen ions. The molarity is half of the normality value.
0.5N sulfuric acid is equivalent to 0.25N sulfuric acid (0.5N/2).
Step 2: Calculate the molarity of sulfuric acid.
To calculate the molarity, you need to know the molecular weight of sulfuric acid, which is 98.09 g/mol.
Molarity (M) = Normality (N) * Equivalent weight (EW)
The equivalent weight of sulfuric acid is the molecular weight divided by the number of hydrogen ions released per molecule, which is 2 for sulfuric acid.
Molarity (M) = 0.25N * (98.09 g/mol) / 2
Step 3: Calculate the volume required for the molarity.
Since you want to prepare a sulfuric acid solution in 500 ml, you need to calculate the mass of the concentrated solution required.
Mass of sulfuric acid (g) = Volume (ml) * Specific gravity * Density
The density of concentrated sulfuric acid is approximately 1.84 g/ml.
Mass of sulfuric acid (g) = 500 ml * 1.84 * 1.00 g/ml
= 920 g
Step 4: Calculate the volume of concentrated sulfuric acid required.
To determine the volume of concentrated sulfuric acid required, you can use the mass calculated in Step 3 and the percent purity given.
Volume (ml) = Mass (g) / (Specific gravity * Density * percent purity/100)
Volume (ml) = 920 g / (1.84 * 1.00 * 98/100)
= 500 ml
Therefore, you need to measure 500 ml of concentrated sulfuric acid with a specific gravity of 1.84 and percent purity of 98. This can be diluted to 500 ml with water to obtain a 0.5N sulfuric acid solution. Please note that concentrated sulfuric acid is highly corrosive and must be handled with caution.
To prepare 0.5N sulfuric acid with specific gravity 1.84 and percent purity 98 in 500 ml, follow these steps:
1. Calculate the molecular weight of sulfuric acid (H2SO4):
- H (hydrogen) has a molecular weight of 1.
- S (sulfur) has a molecular weight of 32.
- O (oxygen) has a molecular weight of 16.
- Multiply the atomic weight of each element by the number of atoms present in sulfuric acid and sum them up:
Molecular weight of H2SO4 = (2 * 1) + (1 * 32) + (4 * 16)
= 2 + 32 + 64
= 98 grams/mole
2. Calculate the amount of sulfuric acid needed to prepare a 0.5N solution:
- 0.5N means that there is 0.5 gram-equivalent weight of solute per liter of solution.
- Since the molecular weight of sulfuric acid is 98 grams/mole, the equivalent weight is equal to the molecular weight divided by the number of acidic hydrogen ions (2 in this case):
Equivalent weight of H2SO4 = Molecular weight of H2SO4 / Number of acidic hydrogen ions
= 98 / 2
= 49 grams/equivalent
3. Calculate the amount of sulfuric acid needed for 500 ml (0.5 liters) of 0.5N solution:
- Multiply the equivalent weight by the number of equivalents needed:
Grams of sulfuric acid needed = Equivalent weight * Number of equivalents
= 49 * 0.5
= 24.5 grams
4. Determine the volume of the sulfuric acid (specific gravity 1.84) required to obtain 24.5 grams of sulfuric acid (98% purity):
- Specific gravity represents the density of a substance relative to the density of water.
- To find the volume of sulfuric acid required, divide the mass by the density:
Volume of sulfuric acid = Mass / Density
= 24.5 grams / (1.84 g/ml)
= 13.3152 ml (approximately)
5. Add this volume (approximately 13.32 ml) of sulfuric acid to a 500 ml measuring flask or container.
6. Fill the container with water up to the 500 ml mark, ensuring complete mixing to prepare a 0.5N sulfuric acid solution.
Remember to handle sulfuric acid with caution as it is a highly corrosive substance and should only be handled by trained individuals using appropriate safety measures.