To determine which volumetric flask to use, we first need to calculate the number of moles of potassium permanganate present in the given amount of salt.
The molar mass of potassium permanganate (KMnO4) is:
- Potassium (K) = 39.10 g/mol
- Manganese (Mn) = 54.94 g/mol
- Oxygen (O) = 16.00 g/mol (x4)
So the molar mass of KMnO4 is:
39.10 + 54.94 + (16.00 x 4) = 158.04 g/mol
Next, we can calculate the number of moles of KMnO4 using the following formula:
moles = mass / molar mass
moles = 3.95 g / 158.04 g/mol
moles = 0.025 mol
To prepare a solution with a concentration of 0.100 mol/dm^3, we multiply the desired concentration by the volume of the solution:
0.100 mol/dm^3 x volume (dm^3) = 0.025 mol
Rearranging the equation, we can solve for the volume in dm^3:
volume (dm^3) = 0.025 mol / 0.100 mol/dm^3
volume (dm^3) = 0.25 dm^3
The volume required is 0.25 dm^3. To convert it to ml, multiply by 1000:
volume (ml) = 0.25 dm^3 x 1000 = 250 ml
Therefore, you should use a volumetric flask with a capacity of 250 ml.
You want to prepare a standard potassium permanganate (KMnO4) solution of concentration 0,100 mol.dm cube .You have 3,95g of salt available.Determine which of these volumetric flask you should use 100ml,200ml,250ml or 500ml. Show all workings
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