This is more of a math question that requires a bit of knowledge of chemistry. So it helps to know the steps of this answer mathematically. Additionally it's worth noting that there are a number of ways to answer this question. The method I provide may take an extra step, but it allows for a better understanding of the process.
First we need to know some basic information about potassium permanganate, KMnO4. This basic information can be found on a Periodic Table, like the one in the link below. The first step is finding the weight of oxygen in one mole of potassium permanganate as a percent. For this you need to know the atomic weights of the elements involved.
K: 39.1 grams
Mn: 54.9 grams
O: 16.0 grams × 4 atoms = 64.0 grams
KMnO4: 39.1 + 54.9 + 64.0 = 158.0 grams/mol
So now we know the weight of one mole of potassium permanganate (158.0 grams). Because we also know the weight of oxygen, we can find the percent of oxygen in the compound by mass.
64.0 grams O ÷ 158.0 grams KMnO4 = 0.405 = 40.5%
In one mole of potassium permanganate, 64.0 grams of it is oxygen, meaning 40.5% of it is oxygen. Because of the Law of Definite Proportions, we know that in any amount of potassium permanganate, 40.5% of it is oxygen.
Then you can set up an equation.
40.5% of (some amount of KMnO4) = 27.5 grams oxygen
Let's set the amount of KMnO4 as the variable "x".
0.405x = 27.5
x = 67.9 grams KMnO4
To calculate the grams of potassium permanganate in 2.20 moles, you would need to know the molar mass of potassium permanganate. The molar mass of potassium permanganate (KMnO4) is about 158.034 g/mol. So, 2.20 moles of KMnO4 is equal to 2.20 moles x 158.034 g/mol = 347.67 grams of potassium permanganate.
The compound potassium permanganate has chemical formula KMnO4 Molecular mass of KMnO4 = 39.1 + 54.9 + 4(16.0) = 158.0 Mass of KMnO4 = amount of KMnO4 x Molecular mass of KMnO4 = 2.55 x 158.0 = 403g
In 2 moles of potassium dichromate, there are 16 moles of oxygen atoms (from the two oxygen atoms in each formula unit). The molar mass of oxygen is 16 g/mol, so in 2 moles of potassium dichromate, there are 32 grams of oxygen.
22 grams of carbon dioxide contains 12 grams of carbon. This amount of carbon can combine with 32 grams of oxygen to form 44 grams of carbon dioxide.
Based on the information provided, you can deduce the initial amount of potassium-40 was 10 grams since half of 10 grams is 5 grams. If there are 5 grams left and the half-life is 1.3 billion years, the rock is approximately 2.6 billion years old.
To calculate the grams of potassium permanganate in 2.20 moles, you would need to know the molar mass of potassium permanganate. The molar mass of potassium permanganate (KMnO4) is about 158.034 g/mol. So, 2.20 moles of KMnO4 is equal to 2.20 moles x 158.034 g/mol = 347.67 grams of potassium permanganate.
To prepare 0.1N potassium permanganate solution, dissolve 3.16 grams of potassium permanganate in 1 liter of water. This will give you a solution with a normality of 0.1N.
To prepare a 0.02 N potassium permanganate solution, you would need to dissolve 1.58 grams of potassium permanganate (KMnO4) in 1 liter of distilled water. This will give you a solution with a molarity of 0.02 N. Remember to wear appropriate personal protective equipment when handling potassium permanganate, as it can be harmful.
To calculate the amount of potassium chlorate needed to produce 112.5g of oxygen, you first need to determine the molar ratio between potassium chlorate and oxygen. Then, use this ratio to convert the grams of oxygen to grams of potassium chlorate using the molar masses of each compound.
There are 6 moles of oxygen atoms in 2 moles of potassium dichromate (K2Cr2O7). Each mole of K2Cr2O7 contains 7 oxygen atoms, so 2 moles would contain 14 oxygen atoms. The molar mass of oxygen is 16 g/mol, so there would be 224 grams of oxygen in 2 moles of K2Cr2O7.
The compound potassium permanganate has chemical formula KMnO4 Molecular mass of KMnO4 = 39.1 + 54.9 + 4(16.0) = 158.0 Mass of KMnO4 = amount of KMnO4 x Molecular mass of KMnO4 = 2.55 x 158.0 = 403g
The molar mass of potassium chlorate (KClO3) is 122.55 g/mol. This means that 122.55 grams of potassium chlorate yield 3 moles of oxygen gas. To calculate the amount of potassium chlorate that decomposes to yield 30 grams of oxygen, you can set up a simple ratio using the molar masses.
The reaction between potassium chlorate and oxygen gas generates potassium chloride and oxygen gas. Therefore, the amount of potassium chlorate produced from the reaction is equal to the amount of potassium chlorate that was used, which is 500 grams.
In 2 moles of potassium dichromate, there are 16 moles of oxygen atoms (from the two oxygen atoms in each formula unit). The molar mass of oxygen is 16 g/mol, so in 2 moles of potassium dichromate, there are 32 grams of oxygen.
To determine the grams of potassium chloride formed, you first need to calculate the moles of oxygen produced by the decomposition of potassium chlorate. Then, use the stoichiometry of the balanced chemical equation to convert moles of oxygen to moles of potassium chloride. Finally, from the molar mass of potassium chloride, you can calculate the grams formed.
In potassium dichromate (K2Cr2O7), there are 7 oxygen atoms per molecule. Therefore, two moles of K2Cr2O7 would contain 14 moles of oxygen atoms. Each mole of oxygen atoms has a molar mass of approximately 16 grams, so there would be 224 grams of oxygen in two moles of potassium dichromate.
The decomposition of potassium chlorate produces oxygen gas and potassium chloride. The molar ratio of oxygen to potassium chlorate is 3:2. Therefore, to find the grams of oxygen produced, you would calculate (6.02g * 3 mol O2/2 mol KClO3) * molar mass of O2.