how many grams of kno3 should be used to prepare

2.00 l of a 0.500m solution

To determine how many grams of KNO3 should be used to prepare a 2.00 L of a 0.500 M solution, we need to use the equation:

Molarity (M) = Moles (mol) / Volume (L)

First, let's rearrange the equation to solve for moles:

Moles (mol) = Molarity (M) x Volume (L)

Now, we can calculate the moles of KNO3 needed:

Moles (KNO3) = 0.500 M x 2.00 L = 1.00 mol

Next, we need to convert moles of KNO3 to grams. To do this, we need to know the molar mass of KNO3. Let's calculate it:

Molar mass of KNO3 = atomic mass of K + atomic mass of N + (3 x atomic mass of O)

Using the periodic table, we find:
Atomic mass of K = 39.10 g/mol
Atomic mass of N = 14.01 g/mol
Atomic mass of O = 16.00 g/mol

Molar mass of KNO3 = 39.10 g/mol + 14.01 g/mol + (3 x 16.00 g/mol)
= 39.10 g/mol + 14.01 g/mol + 48.00 g/mol
= 101.11 g/mol

Finally, we can calculate the grams of KNO3 needed:

Grams = Moles x Molar mass
= 1.00 mol x 101.11 g/mol
= 101.11 g

Therefore, approximately 101.11 grams of KNO3 should be used to prepare 2.00 L of a 0.500 M solution.