- What it is. This hydrogen peroxide is a 35% aqueous solution, supplied in a 1-pint size. It is a clear, colorless, concentrated oxidizer used where slightly higher strength than standard 30% reagent is needed.
- How concentrated it is. At 35% and a density of about 1.13 g/cm³, the solution contains roughly 396 g of H2O2 per liter, about 11.6 M (calculated). It corresponds to about 133 volumes of available oxygen, meaning each volume can release about 133 volumes of oxygen gas on complete decomposition.
- Physical properties. Thirty-five percent hydrogen peroxide boils near 110 °C, freezes near -24 °C, and is mildly acidic (pH 2-4). Its vapor pressure is low at room temperature, but heating releases peroxide and oxygen.
- How it works. Hydrogen peroxide decomposes to water and oxygen, oxidizing organic matter, metals, and many inorganic compounds along the way. Its only by-products are water and oxygen, which makes it attractive for oxidation, bleaching, and disinfection where residues matter.
- Stability and decomposition. Metals, dust, alkalinity, heat, and light accelerate decomposition. Store it cool and dark, keep it clean, and never return unused material to the original container, since contamination can trigger rapid oxygen release and pressure build-up.
- Preparing dilutions. Dilute with deionized water to working strengths: about 1 part 35% plus 10.7 parts water gives roughly 3% (calculated). For an easier ratio, Lab Pro also stocks Hydrogen Peroxide 30 to 32%, 1 pint, and ready-made 3% and 6% solutions.
- Checking concentration. Titration with standardized potassium permanganate in sulfuric acid can confirm peroxide strength. Each mole of permanganate reacts with 2.5 moles of hydrogen peroxide, so the titration gives a direct, accurate measure of the remaining strength.
- Hazards at this strength. Thirty-five percent hydrogen peroxide is harmful if swallowed, causes serious eye damage, irritates the skin and respiratory tract, and can ignite combustible materials it soaks into. Wear goggles, gloves, and a lab coat, and keep it away from organics and metals.
- Where it is used. Thirty-five percent hydrogen peroxide is used in industrial and laboratory oxidation, aseptic processing and sterilization research, wastewater and odor treatment, bleaching of pulp and textiles, semiconductor cleaning, and as a stock for diluted peroxide solutions.
Technical Specifications
| Chemical Name | Hydrogen peroxide, aqueous solution |
| CAS Numbers | 7722-84-1 (hydrogen peroxide); 7732-18-5 (water) |
| EC Number | 231-765-0 |
| Synonyms | Hydrogen dioxide, perhydrol (concentrated), peroxide |
| Formula (active) | H2O2 |
| Molecular Weight (active) | 34.01 g/mol |
| Concentration | 35% |
| Density | About 1.13 g/cm³ (20 °C) |
| Approximate Molarity | About 11.6 M (calculated) |
| Volume Strength | About 133 volumes |
| Boiling Point | About 110 °C |
| Melting Point | About -24 °C |
| pH | About 2 to 4 |
| Appearance | Clear, colorless liquid |
| Hazard Statements (typical) | H302, H315, H318, H335, H412 |
| DOT | UN2014, Hydrogen peroxide, aqueous solution, Class 5.1 (8), PG II |
| Exposure Limit | OSHA PEL and NIOSH REL: 1 ppm TWA |
| Package Size | 1 pint |
Applications / Common Uses
- Oxidation reactions: Oxidizes organic and inorganic substrates.
- Sterilization research: Supports aseptic processing and decontamination studies.
- Wastewater treatment: Oxidizes contaminants and controls odor.
- Bleaching: Whitens pulp, textiles, and other materials.
- Dilution stock: Prepares 3%, 6%, and other strengths.
Storage, Handling & Shipping
Caution: 35% hydrogen peroxide is a strong oxidizer that causes serious eye damage and skin burns, may irritate the respiratory tract, and is harmful if swallowed. It can ignite combustible materials and, when contaminated, decompose, releasing oxygen and heat. Wear chemical splash goggles, gloves, and a lab coat.
Store in the original container in a cool, dark, well-ventilated area away from heat, sunlight, organic materials, metals, and reducing agents. Never return unused peroxide to the original container, since contamination can trigger decomposition that releases oxygen and pressure.
- Incompatible materials: Organic materials, flammables, reducing agents, metals and metal salts (especially iron, copper, chromium, manganese), bases, and dirt or dust.
- Exposure limit: OSHA PEL and NIOSH REL: 1 ppm TWA.
- Spill response: Dilute with large amounts of water and absorb with inert, non-combustible material. Never use sawdust, paper, or other combustibles.
- First aid: Eyes: flush with water for at least 15 minutes and seek immediate medical care. Skin: Rinse thoroughly; temporary skin whitening may occur.
Related Categories & Services
- Shop Oxidizers for related products in this category.
- Explore Oxidizers by Lab Pro and ACS Grade Laboratory Chemicals.
- Vendor Managed Inventory (VMI) Program: Lab Pro can stock, track, and replenish this item on site so it never runs out. Contact info@labproinc.com or 888-452-2776 to set up a VMI assessment.
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FAQs
What does 133 volume hydrogen peroxide mean?
Volume strength describes how much oxygen gas the solution can release. Each volume of 35% hydrogen peroxide can release about 133 volumes of oxygen at standard conditions on complete decomposition. It is a common way to express peroxide strength in industry and cosmetics. Higher volume numbers mean stronger peroxide.
How is 35% different from 30% hydrogen peroxide?
It is about 17% stronger, roughly 11.6 M versus 9.8 M, and releases more oxygen per volume. The hazards are similar, though slightly greater at 35%. The 30% grade is the usual laboratory reagent, while 35% is common in industrial and processing applications. Choose the strength your method specifies.
How do I dilute 35% hydrogen peroxide to 3%?
Mix about 1 part 35% hydrogen peroxide with 10.7 parts deionized water, for example 85.7 mL diluted to 1 liter. Use clean labware, wear goggles and gloves, and label the result. Check strength by titration if your application requires an exact concentration. Always add peroxide to water.
What happens if hydrogen peroxide is contaminated?
Contaminants such as metals, dust, rust, and alkaline materials catalyze decomposition, releasing oxygen and heat. In concentrated solutions this can cause rapid pressure build-up and boiling. Keep peroxide clean, use dedicated labware, and never return unused material to the original container. Dispose of contaminated peroxide safely.
How should 35% hydrogen peroxide be stored?
Store it in its original container in a cool, dark, well-ventilated area away from heat, sunlight, flammables, organic materials, and metals. Keep the area clean and dry, and place it in secondary containment so any leak cannot reach combustible materials. Inspect the storage area regularly for leaks.















