Calculate the mass of K2CRO4 needed to make 3.00 L of a 0.0200 M solution.

First we get the molar mass of K2CrO4. To get the molar mass, just get a periodic table, find the individual masses of the elements and add them all based on the chemical formula. Thus,

K2CrO4: 2*39.1 + 1*52 + 4*16 = 194.2 g/mol
Then recall that molarity is equal to moles of solute per liter of solution, or
M = n/V
Substitute the given values to get n:
0.02 = n / 3
n = 0.06 mol K2CrO4
Finally, multiply this by the molar mass:
0.06 * 194.2 = 11.7 g K2CrO4

Hope this helps~ :3

Thank you!!!!!!!!! :)

Oh, it's chemistry time! Let's solve this equation together. We know that molarity (M) is equal to moles of solute divided by liters of solution. So, we can rearrange this equation to find the moles of solute we need.

Moles of solute = Molarity x Volume

Substituting in the given values:
Moles of solute = 0.0200 mol/L x 3.00 L

Now let's calculate that:
Moles of solute = 0.0600 mol

To find the mass of K2CrO4 needed, we need to multiply the moles of solute by the molar mass of K2CrO4. The molar mass of K2CrO4 is 194.19 g/mol.

Mass of K2CrO4 = Moles of solute x Molar mass
Mass of K2CrO4 = 0.0600 mol x 194.19 g/mol

Calculating that gives us:
Mass of K2CrO4 = 11.65 g (approximately)

So you'll need approximately 11.65 grams of K2CrO4 to make the desired solution.

To calculate the mass of K2CrO4 needed to make a 0.0200 M solution, you need to use the formula:

Molarity (M) = moles of solute / volume of solution (L)

First, let's find the number of moles of solute required.

Moles of solute (K2CrO4) = Molarity (M) x Volume of solution (L)

Moles of solute = 0.0200 M x 3.00 L

Now, we need to find the molar mass of K2CrO4. The molar mass can be calculated by adding up the atomic masses for all the elements in the compound.

Molar mass of K2CrO4 = (2 x atomic mass of K) + atomic mass of Cr + (4 x atomic mass of O)

Using the periodic table, we find:

Atomic mass of K = 39.10 g/mol
Atomic mass of Cr = 52.00 g/mol
Atomic mass of O = 16.00 g/mol

Molar mass of K2CrO4 = (2 x 39.10 g/mol) + 52.00 g/mol + (4 x 16.00 g/mol)

Now, calculate the molar mass:

Molar mass of K2CrO4 = 78.20 g/mol + 52.00 g/mol + 64.00 g/mol

Molar mass of K2CrO4 = 194.20 g/mol

Finally, calculate the mass of K2CrO4 required:

Mass of K2CrO4 = Moles of solute x Molar mass of K2CrO4

Mass of K2CrO4 = (0.0200 M x 3.00 L) x 194.20 g/mol

Now, simply multiply the values:

Mass of K2CrO4 = 0.0600 moles x 194.20 g/mol

Mass of K2CrO4 = 11.65 grams

Therefore, you would need approximately 11.65 grams of K2CrO4 to make a 0.0200 M solution in a 3.00 L volume.