I have been told that to prepare 1L of 70% H2SO4 from concentrated sulphuric acid (96% with density 1.84g/ml), I should use the following equation to find out the volume of conc. acid needed (Vml).
V x 1.84 x 0.96={(1000-V)+ 1.84V}0.7
i.e. V= 594ml of conc H2SO4.
Use 594ml of conc H2SO4 and top up to 1L volumetric flask with water.
Can you please explain this equation to me? Many thanks for your help.
Use the equation:
V1C1 = V2C2
(V1)((0.96) = (1000mls)(0.70)
Solve for V1
After looking at your question more carefully, I changed my mind. The equation, V1C1 = V2C2, works only if the concentrations are ratios of amount of solute over volume of solution. The formula you are using is new to me and since you have made substitutions into it I am not sure what its correct form is.
Your question is not clear either. Are you asking about how to use that formula, or how to derive it?
I would like to know how to derive it, please?
Sure! I'll be happy to explain the equation to you.
The equation you provided is used to calculate the volume of concentrated H2SO4 needed to prepare a 1L solution of 70% H2SO4. Let's break down the equation step by step:
V x 1.84 x 0.96 = (1000 - V) + 1.84V x 0.7
1. The left-hand side of the equation represents the mass of the concentrated H2SO4 you need. We start with the volume of the concentrated acid in milliliters (ml), denoted as V. The density of the concentrated acid is given as 1.84 g/ml, so we multiply V by 1.84 to get the mass in grams. Then, we multiply by 0.96 to account for the concentration of the acid (96%).
2. The right-hand side of the equation represents the total mass of the final solution. It consists of two parts:
- (1000 - V) represents the mass of water needed to make up the 1L final solution. Since the density of water is approximately 1 g/ml and we're working with milliliters, we don't need to multiply it by anything.
- 1.84V x 0.7 represents the mass of the concentrated acid that will be in the final solution after dilution. We multiply the volume (V) by 1.84 to get the mass in grams, and then multiply by 0.7 to account for the desired concentration of 70%.
3. By setting the left-hand side equal to the right-hand side, we are essentially balancing the mass of the concentrated acid with the mass of water and diluted acid in the final solution.
4. Solving the equation will give us the value of V, which represents the volume of concentrated H2SO4 needed in milliliters to prepare a 1L solution of 70% H2SO4.
In this case, the solution is V = 594 ml of concentrated H2SO4. After measuring out this volume of concentrated acid, you can then add water and make up the volume to 1L in a volumetric flask to obtain the desired concentration.
I hope this explanation clarifies the equation for you. Let me know if you have any further questions!