How much volume of 95% alcohol is needed to prepare a 1,000 ml solution of 50% alcohol?

To determine the volume of 95% alcohol needed to prepare 1,000 ml of a 50% alcohol solution, you can apply the concept of dilution and use the formula for mixing solutions, which involves the concentrations and volumes of the two solutions.

For this problem, let’s denote the volume of 95% alcohol needed as V. Since this alcohol is 95% concentrated, the volume of pure alcohol in this portion can be calculated as 0.95V. The resulting solution should have a total volume of 1,000 ml and contain 50% alcohol by volume. Therefore, the amount of pure alcohol in the final 1,000 ml solution should be 50% of 1,000 ml, which is 500 ml.

You can set up the equation as follows:

0.95V = 500 ml

Now, solving for V:

V = 500 ml / 0.95

V ≈ 526.32 ml

Rounding this number, you find that approximately 525 ml of 95% alcohol is needed to achieve the desired concentration of 50% alcohol in the final 1,000 ml solution.

Thus, the correct answer reflects the calculation accurately, ensuring the resulting mixture