Calculate the mass of KH2PO4 (136.09 g/mole) you will need to prepare 450 mL of the 0.05 M solution.

C=m/V
0.05=m/.450L
0.05*.450=m
0.0225=m

Is 0.0225g correct ?

No, 0.0225g is not the correct answer. To calculate the mass needed to prepare the solution, you need to use the formula:

mass = moles x molar mass

First, convert the volume from mL to L:
450 mL = 450/1000 = 0.45 L

Then, use the formula C = moles/L to find the moles of KH2PO4 needed:
0.05 M = moles/0.45 L

Solving for moles gives:
moles = 0.05 M x 0.45 L = 0.0225 moles

Finally, multiply the moles by the molar mass of KH2PO4 to find the mass needed:
mass = 0.0225 moles x 136.09 g/mol ≈ 3.072 g

Therefore, the correct mass of KH2PO4 needed to prepare the 0.05 M solution in 450 mL is approximately 3.072 grams.

No, 0.0225 g is not the correct answer. To calculate the mass of KH2PO4 needed, we can use the formula:

Mass = molarity x volume x molar mass

Given:
Molarity (M) = 0.05 M
Volume (V) = 450 mL = 0.45 L
Molar mass (MM) = 136.09 g/mol

Now, let's substitute these values into the formula:

Mass = 0.05 M x 0.45 L x 136.09 g/mol

Calculating this:

Mass = 3.06 g

Therefore, the mass of KH2PO4 needed to prepare 450 mL of the 0.05 M solution is 3.06 grams.