a solution is made by dissolving 3.95g of NaCl in 78.2 mL what is the concentration of sodium chloride in units of weight/volume percent

To find the concentration of sodium chloride in weight/volume percent, we need to calculate the weight of NaCl (in grams) dissolved in a given volume (in mL) and express it as a percentage.

First, let's convert the volume from milliliters (mL) to liters (L):

78.2 mL = 78.2/1000 L = 0.0782 L

Next, we can calculate the weight/volume percent concentration using the formula:

(weight of NaCl / volume of solution) × 100

(weight of NaCl / 0.0782 L) × 100

Now, we need to find the weight of NaCl. The problem states that we have 3.95g of NaCl dissolved in the solution.

(weight of NaCl / 0.0782 L) × 100 = (3.95g / 0.0782 L) × 100

Now, we can substitute the values into the equation and solve for the concentration:

(3.95 / 0.0782) × 100 = 50.506

So, the concentration of sodium chloride in units of weight/volume percent is approximately 50.506%.