How many moles of solute are present in (1.230x10^1) g of a (5.5x10^0) ppm solution of potassium fluoride? (answer to 2 s.d in mol)
To determine the number of moles of solute in the solution, we first need to convert the given concentration from parts per million (ppm) to moles per liter (mol/L). Here's how you can do it step by step:
Step 1: Convert the mass of the solute to grams.
Given: Mass of solute = 1.230 × 10^1 g
Step 2: Convert the given ppm concentration to grams of solute per liter of solution.
Given: Concentration = 5.5 × 10^0 ppm
To convert from ppm to grams per liter, divide the concentration by 1 million (1,000,000) and multiply by the molar mass of the compound. The molar mass of potassium fluoride (KF) is approximately 58.1 g/mol.
Concentration in g/L = (5.5 × 10^0 ppm / 1,000,000) * 1.230 × 10^1 g / (58.1 g/mol)
Step 3: Calculate the moles of solute.
Moles = Mass (g) / Molar mass (g/mol)
Moles of solute = (1.230 × 10^1 g) / (58.1 g/mol)
Step 4: Round the final answer to two significant figures.
The answer to the question to two significant figures is the final step.
Therefore, the number of moles of solute in the given solution is approximately 0.212 mol.