how many grams of kno3 should be used to prepare
2.00 l of a 0.500m solution
To determine the number of grams of KNO3 needed to prepare a 0.500 M solution in 2.00 L, you need to use the formula:
Molarity (M) = moles of solute / volume of solution (L)
First, we rearrange the formula to solve for moles of solute:
moles of solute = Molarity (M) x volume of solution (L)
Given:
Molarity (M) = 0.500 M
Volume of solution (L) = 2.00 L
Now, we can substitute these values into the formula to calculate the moles of solute:
moles of solute = 0.500 M x 2.00 L
moles of solute = 1.00 mol
The molar mass of KNO3 (potassium nitrate) is:
K: 39.10 g/mol
N: 14.01 g/mol
O: 16.00 g/mol (x 3, since there are three oxygen atoms in KNO3)
Molar mass of KNO3 = 39.10 g/mol + 14.01 g/mol + (16.00 g/mol x 3)
Molar mass of KNO3 = 101.10 g/mol
Finally, we can use the moles of solute calculated to determine the grams of KNO3 needed to make the solution:
grams of KNO3 = moles of solute x molar mass of KNO3
grams of KNO3 = 1.00 mol x 101.10 g/mol
grams of KNO3 = 101.10 g
Therefore, you would need 101.10 grams of KNO3 to prepare 2.00 L of a 0.500 M solution.
To determine the number of grams of KNO3 needed to prepare a 0.500 M solution in a 2.00 L final volume, you need to follow a series of steps:
1. Determine the molar mass of KNO3 (potassium nitrate). The molar mass of KNO3 can be calculated by adding up the atomic masses of each element:
- K (potassium): 39.10 g/mol
- N (nitrogen): 14.01 g/mol
- O (oxygen): 16.00 g/mol (x 3, as there are three oxygen atoms in KNO3)
So, the molar mass of KNO3 is: 39.10 g/mol + 14.01 g/mol + (16.00 g/mol * 3) = 101.10 g/mol.
2. Since you want to prepare a 0.500 M solution, you need to know the moles of KNO3 required using the formula:
Moles (mol) = Molarity (M) × Volume (L)
Moles = 0.500 mol/L × 2.00 L = 1.00 mol
3. Once you have the moles required, you can calculate the grams of KNO3 needed using the formula:
Grams = Moles × Molar mass
Grams = 1.00 mol × 101.10 g/mol = 101.10 grams of KNO3.
Therefore, you would need 101.10 grams of KNO3 to prepare 2.00 liters of a 0.500 M solution.
molarity = # moles/L of solution.
# moles = grams/molar mass.
Use equation 1 first. You know L of solution and molarity; calculate moles.
Then go to equation 2. You know moles and molar mass; calculate grams.