The Atomic Mass of potassium is 39
The atomic mass of chlorine is 35.5
The formula mass of KCl is the sumof these. This is the mass in grams of one mole of KCl. Use this as a conversion factor to find mass of 11 moles
Find molecular weight:
K- 39.1
C- 12.0 × 2= 14.0
H- 1.01 × 3= 3.03
O- 16.0 × 2= 32.0
Total molecular mass: 49.0 grams
Formula of moles ---> grams:
moles × molecular mass
.250 moles × 49.0 grams = 12.3 grams KC2H3O2
The molar mass of K2CO3, or pearl ash, is 138.205 grams per mole. This makes the mass of 0.0112 moles equal to 1.55 grams.
2.02 g
For this you need the atomic (molecular) mass of KCl. Take the number of grams and divide it by the atomic mass. Multiply by one mole for units to cancel. KCl= 74.6 grams50.0 grams KCl / (74.6 grams) = .670 moles KCl
2 KClO3 ------ 2KCl + 3O2 so 2 moles of KClO3 produces two mole of KCl. Therefore 0.440 moles of potassium chlorate will produce 0.44 moles of KCl - potassium chloride.
You have2KClO3 ==> 2KCl + 3O2 as the balanced equation 25 g KClO3 x 1 mole/123 g = 0.20 moles moles KCl formed = 0.20 moles KClO3 x 2 moles KCl/2 moles KClO3 = 0.20 moles KCl formed grams KCl = 0.20 moles x 74.5 g/mole = 14.9 g = 15 grams of KCl formed
2 KClO3 -> KCL + 3O2 Molar weight of O2 = 32 grams/mole (so close it doesn't matter) 30 grams/32grams/mole = 0.9375 moles Molar weight of KCL = 39+35.5 = 74.5 grams/mole (Want more accuracy? Do it yourself?) now if we have 3 moles of O2 then we have 2 moles of KCl. If we have one mole of O2 then we have 2/3 moles of KCL What ever moles we have of O2 we must multiply it by 2/3 to get the moles of KCl So we have 0.9375moles of O2 x 2/3 = 0.625 moles of KCl So 0.625 moles of KCl x 74.5 grams/mole KCl = 46.5625 grams KCl
2.3M means 2.3 moles per litre. Number of moles = 2.3mol/litre x 0.630litre = 1.449mols
KCl has a molar mass of 39+35.5=74.5g/mol, and 48/74.5=0.64mol.
For this you need the atomic (molecular) mass of KCl. Take the number of grams and divide it by the atomic mass. Multiply by one mole for units to cancel. KCl= 74.6 grams50.0 grams KCl / (74.6 grams) = .670 moles KCl
moles KCl = ( M solution ) ( V solution in L )moles KCl = ( 2.2 mol KCl / L solution ) ( 0.635 L of solution )moles KCl = 1.397 moles KCl
moles KCL = ( M solution ) ( L of solution )moles KCl = ( 0.83 mol KCl / L ) ( 1.7 L ) = 1.41 moles KCl
M= moles in solution/liters so plug in what you know 3.0M of KCl solution = moles in solution/ 2.0L multiply both sides by 2.0L moles solute = 1.5 moles KCl so you need 1.5 moles KCl to prepare the solution
In a 3.4 M solution, there are 3.4 moles per liter. If you want to make 3 liters of solution, you'll need 3 liter * 3.4 moles/liter = 10.2 moles The molar mass of KCl is 39.098 g/mole K + 35.453 g/mole Cl = 74.551 g/mole KCl To get the number of grams, multiply the number of moles by the molar mass: 10.2 moles * 74.551 g/mole KCl = 760.4202 g = 0.760 kg
Molarity is moles of solute per L of solution.moles KCl = ( 1.68 M ) ( 0.121 L ) = ( 1.68 mol/L ) ( 0.121 L )moles KCl = 0.203 moles KCl
The formula given shows that each formula unit of KCl contains one atom of potassium. Therefore, the number of moles of potassium will be the same as the number of moles of KCl, and its gram formula mass is 74.55. therefore, the number of moles is 125/74.55 or 1.68, to the justified number of significant digits.
This mass is 631,75 g K2O.
Molarity = moles of solute/Liters of solution 0.75 M KCl = moles KCl/2.25 Liters = 1.6875 moles KCl (74.55 grams/1 mole KCl) = 126 grams of KCl needed
I did not know that you could get a concentration of 75.66 M KCl, but; Molarity = moles of solute/Liters of solution 75.66 M KCl = moles KCl/1 liter = 75.66 moles of KCl 75.66 moles KCl (74.55 grams/1 mole KCl) = 5640 grams KCl that is about 13 pounds of KCl in 1 liter of solution. This is why I think there is something really wrong with this problem!
Molarity = moles of solute/Liters of solution ( 50.0 ml = 0.05 Liters ) 0.552 M KCl = moles/.0.05 liters = 0.0276 moles of KCl