Preparing 1L of 15% Sulfuric Acid from 98% Concentrated Sulfuric Acid

Sulfuric acid, commonly used in various industries, often requires preparations of different concentrations for specific applications. One common task is preparing 1 liter of 15% sulfuric acid (H2SO4) from 98% concentrated sulfuric acid. This guide will explain the detailed process and calculations involved in achieving this concentration.

Understanding the Problem

When preparing dilute sulfuric acid from a concentrated solution, you need to ensure the volume and concentration balance to achieve the desired result. The process starts with understanding the relationship between the density and concentration of each solution.

Calculating the Volume of 98% H2SO4 Required

The key to solving this problem lies in the mathematical principles behind dilution. The formula to calculate the volume of the concentrated solution required to prepare a certain volume of a dilute solution is given by the equation:

{m1 m2}
{rho_{D1}V_1 rho_{D2}V_2}

Where:

ρD1 is the density of the concentrated solution (98% H2SO4) ρD2 is the density of the diluted solution (15% H2SO4) V1 is the volume of the concentrated solution needed V2 is the final volume (1 liter in this case)

Given:

ρD1 1.84 g/mL (98% H2SO4) ρD2 1.102 g/mL (15% H2SO4) V2 1000 mL (1 liter)

The equation becomes:

{1.84 g/mL times; V_1 1.102 g/mL times; 1000 mL}

Solving for V1 gives:

{V_1 frac{1.102 g/mL times; 1000 mL}{1.84 g/mL} 600 mL}

However, the student provided a different calculation which led to V1 91.7 mL. Let's follow that calculation to see if it is correct:

{0.98 times; 1.84 V_1 0.15 times; 1.102 times; 1000 mL} {1.50912 V_1 165.3} {V_1 frac{165.3}{1.50912} 91.7 mL}

This confirms the original calculation of 91.7 mL of 98% H2SO4 is required.

Practical Steps for Preparation

The practical steps to prepare 1 liter of 15% sulfuric acid from 98% concentrated sulfuric acid are as follows:

Mixing and Dilution: Carefully measure 91.7 mL of the 98% concentrated sulfuric acid and slowly dilute it with water to a final volume of 1 liter. It's crucial to perform this in a well-ventilated area and use proper safety equipment such as gloves and goggles. Mixing: Gently mix the acid and water using a stirrer or magnetic stirring to ensure the solution is homogeneous. Storage: Store the prepared 15% sulfuric acid in a appropriate container away from sources of heat or direct sunlight.

Important Safety Considerations

Handling sulfuric acid is extremely dangerous and should only be attempted by trained professionals. The high concentration of sulfuric acid can cause severe burns, damage to eye and respiratory systems, and other injuries. Proper safety measures include:

Wear protective clothing including gloves, goggles, and lab coat. Work in a well-ventilated area or fume hood. Ensure the use of appropriate tools and have access to safety showers and eyewash stations. Always add acid to water, never the reverse.

Frequently Asked Questions

Why is it important to always add acid to water? Dilution of acid into water releases heat which can cause splashing. Adding acid to water minimizes this risk. Can I use any container for this preparation? No, only use appropriate containers that can withstand the concentration and temperature changes. Glass containers are common, but plastic or metallic containers must be avoided as they may react with sulfuric acid. What is the significance of the 15% concentration? The concentration of the sulfuric acid influences its application in various industries. A 15% solution is often used in battery manufacturing, chemical processing, and other industrial applications.

Understanding the process of preparing sulphuric acid solutions is crucial for both safety and efficiency in chemical operations. By following these steps and safety guidelines, you can successfully prepare 1 liter of 15% sulfuric acid from 98% concentrated sulfuric acid.