What mass of sodium chloride, NaCl, is needed to make 369. g of a 3.04%(m/m) NaCl solution?
(atomic masses: Na = 22.99, Cl = 35.45)
% w/w = mass solute/mass solution.
(X/369)*100 = 3.04
Solve for X = grams NaCl.
massNaCl=369*.0304
To find the mass of sodium chloride (NaCl) needed to make a 3.04% (m/m) NaCl solution, you need to determine the amount of NaCl in grams that makes up 3.04% of the total solution mass.
Let's break down the steps to get the answer:
Step 1: Identify the known values
- Mass of the solution = 369 g
- Percentage of NaCl (m/m) = 3.04%
- Atomic mass of sodium (Na) = 22.99 g/mol
- Atomic mass of chlorine (Cl) = 35.45 g/mol
Step 2: Convert the percentage to a decimal
To convert the percentage to a decimal, divide it by 100:
3.04% = 3.04/100 = 0.0304
Step 3: Calculate the mass of NaCl in the solution
To calculate the mass of NaCl, multiply the mass of the solution by the decimal representing the percentage of NaCl:
Mass of NaCl = Mass of solution × Percentage of NaCl (decimal)
Mass of NaCl = 369 g × 0.0304
Step 4: Convert the mass of NaCl from moles to grams
Since we have the atomic masses of Na and Cl, we can calculate the molar mass of NaCl and then convert the mass from moles to grams.
Molar mass of NaCl = (atomic mass of Na) + (atomic mass of Cl)
Molar mass of NaCl = 22.99 g/mol + 35.45 g/mol = 58.44 g/mol
To convert the mass of NaCl from moles to grams, divide the mass in moles by the molar mass:
Mass of NaCl in grams = (Mass of NaCl in moles) × (Molar mass of NaCl)
Mass of NaCl in grams = (369 g × 0.0304) / 58.44 g/mol
Calculating this expression will give you the mass of NaCl needed to make 369 g of a 3.04% NaCl solution.