The molar mass of hydrogen fluoride, HF, is 20.0 g/mol. If 17.0 grams of HF are dissolved in water
to give 200.0 mL of solution, what is the molarity of this solution?
mols = grams/molar mass = ?. Then
M = mols/L solution.
i don't know which numbers to plug in where. this is what i was given in my intro to chem class and i am totally lost.
would it be 17/20.0=?
4.25
To find the molarity of a solution, you need to know the number of moles of solute (in this case, HF) and the volume of solution in liters.
First, let's calculate the number of moles of HF present in 17.0 grams using the molar mass of HF.
Molar mass of HF = 20.0 g/mol
Mass of HF = 17.0 grams
Number of moles of HF = Mass of HF / Molar mass of HF
= 17.0 g / 20.0 g/mol
Next, we need to convert the volume of the solution from milliliters (mL) to liters (L).
1 liter = 1000 milliliters
Therefore, 200.0 mL = 200.0 mL * (1 L / 1000 mL) = 0.200 L
Now, we have the number of moles of HF and the volume of the solution in liters. We can calculate the molarity using the formula:
Molarity (M) = Moles of solute / Volume of solution in liters
Molarity (M) = (Number of moles of HF) / (Volume of solution in liters)
= (17.0 g / 20.0 g/mol) / 0.200 L
Simplifying the calculation:
Molarity of solution = 0.85 mol / 0.200 L
= 4.25 mol/L
Therefore, the molarity of the solution is 4.25 mol/L or 4.25 M.