Which of the follwoing gives the molarity of 17.0% by mass solution of sodium acetate (molar mass = 82.0 g/mol) in water. The density of the solution is 1.09 g/mL.

OK - I know that to figure molarity is moles divided by liters. This is confusing me because it is "17.0% by mass" I don't understand this. How much water are you using? I have a list of answers, but the answers won't do me any good if I don't know how I got there. HELP!!!

assume you have one liter. Then the mass of the solution is 1090 grams. Seventeen percent of that is mass solute. The rest is water.

To determine the molarity of a solution, you need to know the amount of solute (in moles) and the volume of the solution (in liters). Starting with the given information, here's the step-by-step process:

1. Determine the amount of solute (sodium acetate) in grams:
- Since the solution is "17.0% by mass," it means that 17.0 grams of sodium acetate are present in 100 grams of the solution.
- To find the mass of sodium acetate in the solution, you can assume you have 100 grams of the solution, as the percentage composition is given with respect to the mass.
- Therefore, the mass of sodium acetate in the solution is (17.0/100) * 100 grams = 17.0 grams.

2. Calculate the moles of sodium acetate:
- To find the moles of sodium acetate, divide the mass (in grams) by the molar mass (82.0 g/mol):
- Moles = 17.0 grams / 82.0 g/mol = 0.2073 moles.

Now, we need to determine the volume of the solution (in liters):

3. Calculate the volume of the solution:
- The density of the solution is given as 1.09 g/mL.
- To convert this to liters, divide by 1000 (since 1 mL = 0.001 L):
- Volume = 1.09 g/mL / 1000 mL/L = 0.00109 L.

Now that we have the amount of solute (moles) and the volume of the solution (liters), we can find the molarity:

4. Calculate the molarity:
- Molarity (M) = Moles / Volume
- Molarity = 0.2073 moles / 0.00109 L
- Molarity ≈ 190.18 M (rounded to two decimal places).

Therefore, the molarity of the 17.0% by mass solution of sodium acetate in water is approximately 190.18 M.

To calculate the molarity of a solution, you first need to understand what it means for a solution to be "17.0% by mass" sodium acetate. This refers to the amount of sodium acetate present in the solution relative to the total mass of the solution.

To solve this problem, you have the following information:
- Percentage by mass: 17.0%
- Molar mass of sodium acetate: 82.0 g/mol
- Density of the solution: 1.09 g/mL

First, let's understand the concept of "17.0% by mass." This means that for every 100 grams of the solution, 17 grams of it is sodium acetate. The remaining 83 grams are water.

Now, let's determine how much sodium acetate is present in the solution in grams. We know that the solution is 17.0% sodium acetate by mass, and the total mass of the solution can be calculated using the density. The density is given as 1.09 g/mL, which means that for every milliliter (mL) of the solution, there is 1.09 grams of it.

Let's assume you have 100 mL of the solution. To calculate the mass of the solution, you can multiply the volume (100 mL) by the density (1.09 g/mL):

Mass of solution = Volume × Density
Mass of solution = 100 mL × 1.09 g/mL
Mass of solution = 109 g

Now that we know the mass of the solution, we can calculate the mass of sodium acetate in it. Since the solution is 17.0% sodium acetate by mass, we can calculate the mass of sodium acetate as follows:

Mass of sodium acetate = Percentage by mass × Mass of solution
Mass of sodium acetate = 17.0% × 109 g
Mass of sodium acetate = 0.17 × 109 g
Mass of sodium acetate = 18.53 g

Now, we need to convert the mass of sodium acetate to moles by dividing it by the molar mass of sodium acetate:

Moles of sodium acetate = Mass of sodium acetate / Molar mass
Moles of sodium acetate = 18.53 g / 82.0 g/mol
Moles of sodium acetate ≈ 0.226 mol

Finally, to calculate the molarity, divide the moles of sodium acetate by the volume of the solution in liters:

Molarity = Moles of sodium acetate / Volume of solution (in liters)
Molarity = 0.226 mol / 0.1 L
Molarity = 2.26 M

So, the molarity of the 17.0% by mass solution of sodium acetate in water is approximately 2.26 M.

Keep in mind that the volume of the solution used in the calculation should be adjusted according to the specific problem or instructions given.