A 3.4g sample of h2o2 solution containing x% H2O2 by mass requires x ml of a KMnO4 solution for complete oxidation under acidic condition. The molarity of KMnO4 solution is:
a)1
b)0.5
c)0.4
d)0.2
To find the molarity of the KMnO4 solution, we need to use the concept of stoichiometry and balancing equations.
First, let's write and balance the equation for the reaction between H2O2 and KMnO4 in acidic conditions:
H2O2 + KMnO4 → O2 + H2O + Mn2+
From the balanced equation, we can see that the molar ratio between H2O2 and KMnO4 is 1:1. This means that for every 1 mole of H2O2, 1 mole of KMnO4 is required to react completely.
Given that a 3.4g sample contains x% H2O2 by mass, we need to convert this mass to moles using the molar mass of H2O2.
The molar mass of H2O2 is:
(2*1.01 g/mol for hydrogen) + (2*16.00 g/mol for oxygen) = 34.02 g/mol
To find the moles of H2O2 in the 3.4g sample, we can use the following formula:
moles = mass / molar mass
moles of H2O2 = 3.4g / 34.02 g/mol
Now, since the molar ratio between H2O2 and KMnO4 is 1:1, the moles of KMnO4 required for the reaction is also equal to the moles of H2O2.
Next, we need to find the volume of the KMnO4 solution required for complete oxidation. According to the question, x ml of the KMnO4 solution is needed.
Finally, to find the molarity (M) of the KMnO4 solution, we need to use the formula:
Molarity = moles / volume
Molarity = moles of KMnO4 / volume of KMnO4 solution (in L)
Substituting the values into the formula, we get:
Molarity = moles of KMnO4 / (x * 0.001 L) (since 1 mL = 0.001 L)
Therefore, we can conclude that the molarity of the KMnO4 solution is equal to the moles of KMnO4 divided by the volume of the KMnO4 solution in liters.