Describe in detail how you would make 1.25 of 0.125 M potassium permanganate solution.
I think you have to set up an equation for molarity but I'm not sure. Please help.
To make a 1.25 L solution of 0.125 M potassium permanganate (KMnO4), you need to follow a few steps.
First, let's understand what the terms "1.25 L" and "0.125 M" mean:
1.25 L stands for 1.25 liters, which is the desired volume of the solution you want to make.
0.125 M stands for 0.125 moles per liter, which is the desired concentration of potassium permanganate in the solution.
To calculate how much potassium permanganate you need, you can use the formula:
moles = concentration × volume
In this case, you can rearrange the formula to solve for moles:
moles = 0.125 M × 1.25 L
moles = 0.15625 mol
Now that we know the number of moles required, we can use the molar mass of potassium permanganate to calculate the mass needed. The molar mass of KMnO4 is:
K (potassium) = 39.10 g/mol
Mn (manganese) = 54.94 g/mol
O (oxygen) = 16.00 g/mol (four oxygen atoms in KMnO4)
Total molar mass = (1 × 39.10 g/mol) + (1 × 54.94 g/mol) + (4 × 16.00 g/mol) = 158.04 g/mol
Now, using the moles calculated earlier:
mass = moles × molar mass
mass = 0.15625 mol × 158.04 g/mol
mass ≈ 24.69 g
Therefore, to make a 1.25 L solution of 0.125 M potassium permanganate, you need approximately 24.69 grams of potassium permanganate. Measure this amount accurately, dissolve it in water, and then bring the total volume of the solution up to 1.25 liters.