How many grams of LiOH would be needed to make a 500.0 mL of 0.340 M LiOH?
How many moles LiOH do you need? That will be moles = M x L = ?
Then moles = grams/molar mass
You know moles and molar mass, solve for grams.
To find out how many grams of LiOH are needed to make a 500.0 mL of 0.340 M LiOH solution, you will need to use the formula:
Molarity (M) = moles of solute / volume of solution (in liters)
First, convert the given volume of the solution from milliliters (mL) to liters (L):
500.0 mL ÷ 1000 = 0.500 L
Next, rearrange the formula to solve for moles of solute:
moles of solute = Molarity (M) × volume of solution (in liters)
Now, substitute the given values:
moles of solute = 0.340 M × 0.500 L
Calculate the moles of solute:
moles of solute = 0.170 mol
Since the question asks for grams of LiOH, use the molar mass of LiOH to convert moles to grams:
Molar mass of LiOH = (6.941 g/mol of Li) + (15.9994 g/mol of O) + (1.00794 g/mol of H) = 23.94734 g/mol of LiOH
Finally, multiply the moles of solute by the molar mass to get the mass of LiOH:
mass of LiOH = moles of solute × molar mass of LiOH
mass of LiOH = 0.170 mol × 23.94734 g/mol of LiOH
mass of LiOH ≈ 4.069 g (rounded to three decimal places)
Therefore, approximately 4.069 grams of LiOH would be needed to make a 500.0 mL of 0.340 M LiOH solution.