Please help.
Concentrated hydrochloric acid is a 38% w/w solution of HCL in water and has a density of 1.18g/ml. How many millilitres of concentrated hydrochloric acid are needed to prepare 500ml of a 1:200 w/v HCL solution?
My answer is 2.12ml. I'm not sure if its correct. Please help.
give the following word concetrated
To find the correct answer, you need to follow a step-by-step approach. Let's break it down:
1. Calculate the mass of HCl in 500 ml of a 1:200 w/v solution:
The ratio 1:200 means that there is 1 part HCl in every 200 parts of the solution.
Therefore, to calculate the mass of HCl in the solution, we need to divide the total volume (500 ml) by the denominator of the ratio (200).
Mass of HCl = (Volume of solution / Denominator of ratio) * Numerator of ratio
Mass of HCl = (500 ml / 200) * 1
Mass of HCl = 2.5 g
2. Calculate the volume of concentrated hydrochloric acid needed:
Concentrated hydrochloric acid is a 38% w/w solution, meaning that it contains 38 grams of HCl in 100 grams of solution.
So, we need to calculate how much of this solution contains 2.5 grams of HCl.
Volume of concentrated hydrochloric acid = (Mass of HCl / % w/w) * 100
Volume of concentrated hydrochloric acid = (2.5 g / 38%) * 100
Volume of concentrated hydrochloric acid = 6.58 ml (rounded to two decimal places)
Therefore, the correct answer is approximately 6.58 ml of concentrated hydrochloric acid are needed to prepare 500 ml of a 1:200 w/v HCl solution. So, your initial answer of 2.12 ml is incorrect.