The role of a reagent bottle in a laboratory is to store, protect and dispense chemical reagents safely while keeping them pure and at their stated concentration. A reagent bottle is a container, usually made of borosilicate 3.3 glass or chemical-resistant plastic, used to hold liquid or solid chemicals. It protects reagents from light, air, moisture and contamination, allows controlled pouring, and carries the label that identifies the chemical and its hazards. Narrow-mouth bottles suit liquids and wide-mouth bottles suit solids, and amber glass shields light-sensitive reagents. Edu Lab China manufactures the lab glassware, including reagent bottles, used for chemical storage.
| What is the role of a reagent bottle in a laboratory? A reagent bottle stores chemical reagents and protects them from light, air, moisture and contamination so they stay pure and keep their stated concentration. Narrow-mouth reagent bottles are used for liquids and reduce evaporation, while wide-mouth bottles are used for solids and powders. Amber (actinic) glass blocks light up to about 500 nm to protect light-sensitive reagents such as silver nitrate and potassium permanganate. Borosilicate 3.3 glass suits most chemicals, but hydrofluoric acid needs a plastic bottle. The bottle also carries the GHS hazard label. Browse lab glassware and lab chemicals for related supplies. |
What is a reagent bottle?
A reagent bottle is a laboratory container used to store and dispense chemical reagents in liquid or solid form, typically made of borosilicate 3.3 glass or chemical-resistant plastic and fitted with a stopper or screw cap. A reagent bottle is a type of laboratory glassware whose design — neck width, colour, material and closure — is chosen to suit the chemical it holds. The international standard for laboratory glass bottles is ISO 4796, with ISO 4796-1:2016 covering screw-neck bottles for general laboratory use.
What are the roles of a reagent bottle in a laboratory?
The roles of a reagent bottle are to store reagents, protect them from light and air, control contamination, allow safe dispensing, identify the chemical and preserve its concentration. A reagent bottle does more than hold a chemical: it actively keeps the reagent unchanged from the moment it is filled to the moment it is used. The table lists each role and why it matters.
| Role | What it does | Why it matters |
| Storage | Holds liquid or solid reagents | Keeps chemicals contained and organised |
| Protection from light | Amber glass blocks UV and visible light | Prevents photolysis of light-sensitive reagents |
| Protection from air and moisture | Sealed stopper or screw cap | Prevents oxidation, evaporation and hydration |
| Contamination control | Inert, cleanable inner surface | Maintains reagent purity |
| Controlled dispensing | Narrow neck or pouring ring | Pours without spill or splash |
| Identification | Enamel marking spot or label area | Supports GHS labelling and traceability |
| Concentration stability | Airtight, light-proof storage | Keeps the stated concentration accurate |
| Chemical containment | Chemically resistant material | Safely holds acids, alkalis and solvents |
Caption: The roles of a reagent bottle in a laboratory, with what each role does and why it matters.
What are the types of reagent bottle?
The main types of reagent bottle are narrow-mouth and wide-mouth bottles, in clear or amber glass, made of borosilicate glass or chemical-resistant plastic, plus the dropping bottle for small volumes. The type is chosen from the state of the reagent and its sensitivity to light and chemicals. The table compares the types and what each is best used for.
| Type | Distinguishing feature | Best for | Note |
| Narrow-mouth (narrow-neck) | Tapered narrow neck | Liquids, solvents, acids, titrants | Reduces evaporation; precise pouring |
| Wide-mouth | Wide opening | Solids, powders, viscous reagents | Easy filling and scooping |
| Clear (colourless) glass | Transparent | Light-stable reagents; visibility | Maximum content visibility |
| Amber (actinic) glass | Brown tint | Light-sensitive reagents | Blocks light up to ~500 nm |
| Glass reagent bottle | Borosilicate 3.3 | Most chemicals; solvents; heat | Inert; autoclavable |
| Plastic reagent bottle | HDPE / LDPE / PP | Hydrofluoric acid; alkalis; field use | Unbreakable; not for strong oxidisers |
| Dropping bottle | Integral dropper | Indicators; drop-by-drop dispensing | Small, controlled delivery |
Caption: The types of reagent bottle and what each is best used for, by mouth width, colour and material.
Why are some reagent bottles amber or coloured?
Some reagent bottles are amber (actinic) because amber glass filters out ultraviolet and short-wavelength visible light up to about 500 nm, protecting light-sensitive reagents from photolysis. Photolysis is the breakdown of a chemical by light energy, which weakens, discolours or alters the reagent so it no longer matches its label. Potassium permanganate, silver nitrate, iodine and hydrogen peroxide are common light-sensitive reagents stored in amber bottles. Intrinsic amber glass is used rather than clear glass wrapped in foil, because the colour is built into the glass and cannot be displaced.
What materials and closures are used for reagent bottles?
Reagent bottles are made from borosilicate 3.3 glass, soda-lime glass or chemical-resistant plastics such as HDPE and polypropylene, and are closed with ground-glass stoppers or GL45 screw caps. The material must resist the chemical stored, and the closure must seal it without reacting or seizing. The table sets out the common materials and closures, their property, best use and what to avoid.
| Material / closure | Property | Best use | Avoid with |
| Borosilicate 3.3 glass | Inert; thermal-shock resistant | Acids, solvents, most reagents | Hydrofluoric acid (etches glass) |
| Soda-lime glass | Lower cost; less resistant | Non-aggressive storage | Strong or hot chemicals |
| HDPE / LDPE | Chemical-resistant plastic | Hydrofluoric acid; alkalis; field samples | Strong oxidisers; high heat |
| Polypropylene (PP) | Autoclavable to ~140 C | Sterile media; reusable bottles | Some organic solvents |
| Ground-glass stopper | Interchangeable; airtight | Volatile liquids; long storage | Alkalis (NaOH/KOH seize the joint) |
| PP screw cap (GL45) | Interchangeable; sealed | Routine storage and dispensing | — |
Caption: Reagent bottle materials and closures, their property, best use and what to avoid each with.
What specifications should you check before buying reagent bottles?
Before buying reagent bottles, check the material, mouth type, colour, thread or closure, capacity and standard compliance. The single most important specification is the material, because it must resist the chemicals the bottle will hold. The GL45 screw thread is the most widely supported laboratory bottle format, with interchangeable caps and pouring rings across sizes. The table lists the specifications to verify and a typical value or reference.
| Specification | What to check | Typical value / reference |
| Material | Borosilicate 3.3 or chemical-grade plastic | ISO 3585 / USP Type I (glass) |
| Mouth type | Narrow for liquids, wide for solids | Match to reagent state |
| Colour | Clear or amber | Amber for light-sensitive (~500 nm) |
| Thread / closure | Standard interchangeable thread | GL45 (ISO 4796-1:2016) |
| Capacity | Sized to the reagent volume | 30 mL to 20 000 mL common |
| Graduations | Approximate only | About +/-10% (not for accurate measuring) |
| Standard compliance | Conforms to the bottle standard | ISO 4796-1 / ISO 4796-2 |
Caption: Specifications to verify before buying reagent bottles, with a typical value or governing reference for each.
Which reagent bottle should you use for which reagent?
Choose a reagent bottle by the reagent’s state, its light sensitivity, its chemical compatibility and the required closure. Matching the bottle to the reagent prevents both reagent degradation and bottle failure, such as an alkali fusing a glass stopper shut. The decision rule below makes the choice explicit, and the matrix applies it to common reagents.
The Reagent-Bottle Selection Rule: choose a reagent bottle by four properties in order. (1) State: narrow-mouth for liquids, wide-mouth for solids. (2) Light sensitivity: amber glass for light-sensitive reagents such as silver nitrate and potassium permanganate. (3) Chemical compatibility: borosilicate glass for most reagents, but HDPE or PTFE plastic for hydrofluoric acid, and a plastic or rubber stopper rather than a ground-glass stopper for strong alkalis. (4) Closure: a ground-glass stopper for volatile liquids and airtight storage, or a GL45 screw cap for routine use.
| Reagent / property | Mouth | Colour | Material / closure |
| Dilute acids (HCl, H2SO4) | Narrow | Clear | Borosilicate; glass or PP stopper |
| Light-sensitive (AgNO3, KMnO4, I2, H2O2) | Narrow | Amber | Borosilicate; stopper |
| Strong alkalis (NaOH, KOH) | Narrow or wide | Clear | Plastic or rubber stopper (not ground glass) |
| Hydrofluoric acid (HF) | Narrow | Clear | HDPE or PTFE plastic (never glass) |
| Solid / powder reagents | Wide | Clear or amber | Borosilicate; screw cap |
| Volatile solvents | Narrow | Clear or amber | Borosilicate; ground-glass stopper |
| Indicators / small volumes | Dropper | Amber or clear | Dropping bottle |
Caption: The Reagent-Bottle Selection Rule applied to common reagents, giving the mouth, colour and material or closure for each.
How do you store and handle reagents in bottles safely?
Store and handle reagents in bottles safely by labelling every bottle, using amber bottles for light-sensitive reagents, matching the material and closure to the chemical, keeping caps tight, and segregating incompatible reagents. Safe storage protects both the reagent and the people in the laboratory. The table lists the key practices, why each matters and the reference.
| Practice | Why it matters | Reference |
| Label with GHS pictogram, name, concentration and date | Prevents mis-identification | GHS Rev. 11 (2025) |
| Store light-sensitive reagents in amber bottles | Prevents photolysis | Light-protection practice |
| Use plastic for hydrofluoric acid; never glass | Hydrofluoric acid etches glass | Chemical compatibility |
| Avoid ground-glass stoppers with alkalis | Alkalis seize and fuse the joint | Chemical compatibility |
| Keep caps tight and store bottles upright | Prevents leaks and evaporation | Storage practice |
| Segregate incompatible reagents | Prevents dangerous reactions | Laboratory chemical-storage policy |
| Do not use bottle graduations for accurate volumes | Graduations carry ~+/-10% error | Use volumetric glassware instead |
Caption: Safe storage and handling practices for reagents in bottles, with the reason and reference for each.
1. Select the correct bottle type, colour and material for the reagent, using the Reagent-Bottle Selection Rule.
2. Clean and dry the bottle before filling it.
3. Fill to a safe level, leaving headspace for thermal expansion.
4. Fit the correct closure: a ground-glass stopper for volatiles, a GL45 cap for routine use, or a plastic stopper for alkalis.
5. Label the bottle with the reagent name, concentration, GHS hazard pictogram and date.
6. Store light-sensitive reagents in amber bottles, away from direct light.
7. Store bottles upright with caps tight, segregating incompatible chemicals.
8. Inspect periodically for seized stoppers, cracks and degraded labels.
9. Do not rely on the bottle’s graduations for accurate measurement.
10. Record reagent receipt, transfer and disposal in the laboratory inventory.
Caption: A ten-step reagent-bottle filling, labelling and storage checklist for safe chemical handling.
“The two failures I see most with reagent bottles are a clear bottle used for silver nitrate, which darkens within weeks, and a ground-glass stopper fused solid onto a bottle of sodium hydroxide. Both are avoided by one habit: choose the bottle for the chemical, not whatever is on the shelf.” — Arvind Kumar, Lab Equipment Specialist (12+ years), reviewer of this guide.
How do reagent bottles match the lab level?
Reagent bottles scale with the laboratory level: small clear and amber bottles and plastic for primary and middle school, a standard glass reagent set for high school, ground-glass-stoppered bottles for college, and GL45 media bottles plus plastic for hydrofluoric acid at university. Matching the range to the level keeps younger labs simple while giving research labs the chemical-compatibility options they need. Map the reagent set to the practical syllabus in use, such as Gaokao (NCEE), Cambridge/IB or a Ministry of Education curriculum, and confirm the current syllabus edition before citing it in a specification.
| Level | Typical reagent bottles | Note |
| Middle / primary school | Small clear and amber narrow-mouth; plastic | Limited reagents; teacher-controlled |
| High school | Narrow and wide-mouth glass; amber for light-sensitive | Standard reagent set |
| College / pre-university | Full range including ground-glass-stopper bottles | Quantitative reagents |
| University / research | GL45 media bottles; amber; plastic for HF | Media prep and analytical reagents |
Caption: How reagent bottles match the laboratory level, from primary-school science to university research.
Vendor evaluation criteria for reagent bottles
Evaluate reagent-bottle vendors on a weighted scorecard that prioritises material and chemical resistance, standard compliance and closure quality over price. The weighting below places the greatest emphasis on the factors that determine whether the bottle safely holds the reagent and keeps it unchanged.
| Criterion | What to assess | Weighting (%) |
| Material and chemical resistance | Borosilicate 3.3 or chemical-grade plastic | 25% |
| Standard compliance | ISO 4796-1; GL45 thread | 20% |
| Closure quality and interchangeability | Stoppers and caps seal and interchange | 20% |
| Amber light protection | Intrinsic amber glass, not a coating | 15% |
| Marking and graduation durability | Permanent enamel marking spot | 10% |
| Packing and export logistics | Breakage-safe packing; lead time | 10% |
Caption: A weighted vendor evaluation scorecard for reagent bottles, totalling 100%.
Common mistakes when choosing or using reagent bottles
Mistake 1: Storing light-sensitive reagents in clear bottles
Storing reagents such as silver nitrate or potassium permanganate in clear glass lets light degrade them through photolysis, changing their concentration. Use intrinsic amber bottles, which block light up to about 500 nm, for all light-sensitive reagents.
Mistake 2: Using a ground-glass stopper with sodium hydroxide
Strong alkalis such as sodium hydroxide react with the ground-glass joint and fuse the stopper into the neck, making the bottle impossible to open. Store alkalis in bottles with a plastic or rubber stopper, never a ground-glass one.
Mistake 3: Storing hydrofluoric acid in glass
Hydrofluoric acid etches and dissolves glass, so a glass reagent bottle is unsafe for it. Store hydrofluoric acid only in HDPE or PTFE plastic bottles designed for the purpose.
Mistake 4: Relying on bottle graduations for accurate volumes
Reagent-bottle graduations are approximate, often with around 10% error, so they cannot be used for accurate measurement. Measure accurate volumes with volumetric glassware such as a pipette, burette or volumetric flask.
Mistake 5: Leaving bottles unlabelled or undated
An unlabelled or undated reagent bottle cannot be identified safely and may be used past its useful life. Label every bottle with the reagent name, concentration, GHS hazard pictogram and date of preparation.
Mistake 6: Storing incompatible reagents together or overfilling
Storing incompatible reagents side by side, or overfilling a bottle, risks dangerous reactions and leaks. Segregate incompatible chemicals per the laboratory storage policy and leave headspace for thermal expansion.
Related resources and category pages
• Full educational and scientific lab equipment catalogue
Frequently asked questions
What is a reagent bottle used for?
A reagent bottle is used to store and dispense chemical reagents while protecting them from light, air, moisture and contamination. Narrow-mouth reagent bottles hold liquids and reduce evaporation, while wide-mouth bottles hold solids and powders. The bottle also carries the GHS hazard label that identifies the chemical and its concentration. Most reagent bottles are borosilicate 3.3 glass, with plastic used for chemicals such as hydrofluoric acid; browse the lab glassware range for options.
What reagent bottles do schools need for chemistry?
Schools need a set of narrow-mouth and wide-mouth glass reagent bottles, with amber bottles for light-sensitive reagents and plastic bottles for chemicals that attack glass. Narrow-mouth bottles are used for liquid reagents and wide-mouth bottles for solids. Align the reagent set with the practical syllabus in use, such as Gaokao (NCEE), Cambridge/IB or a Ministry of Education curriculum, and confirm the current syllabus edition before finalising a specification. Source bottles and reagents from the lab chemicals range.
Why are some reagent bottles amber or brown?
Some reagent bottles are amber or brown because the coloured glass filters out ultraviolet and short-wavelength visible light up to about 500 nm, protecting light-sensitive reagents from photolysis. Photolysis breaks chemical bonds using light energy, weakening or altering the reagent. Chemicals such as silver nitrate, potassium permanganate, iodine and hydrogen peroxide are kept in amber bottles for this reason. Intrinsic amber glass is preferred over clear glass wrapped in foil because the protection cannot be displaced.
Are glass or plastic reagent bottles better for a lab?
Glass reagent bottles are better for most reagents because borosilicate 3.3 glass is chemically inert, heat-resistant and easy to clean, while plastic bottles are better for chemicals that attack glass and where breakage is a concern. Hydrofluoric acid and strong alkalis are stored in HDPE or polypropylene plastic, and plastic is also useful for fieldwork. Choose the material from the chemical stored rather than by default. Request a current quotation in your local currency (for example Renminbi or USD), include any taxes or import duty, and verify pricing before procurement.
Why does a glass stopper get stuck in a reagent bottle?
A glass stopper gets stuck in a reagent bottle when an alkali reacts with the ground-glass joint and fuses the stopper to the neck, or when evaporated reagent crystallises in the joint. Strong alkalis such as sodium hydroxide are the most common cause, which is why they should be stored with plastic or rubber stoppers instead. Lightly greasing the joint and avoiding alkalis in ground-glass-stoppered bottles prevents seizing.
What’s the difference between a narrow-mouth and wide-mouth reagent bottle?
A narrow-mouth reagent bottle has a tapered neck for liquids, reducing evaporation and allowing precise pouring, while a wide-mouth bottle has a large opening for solids, powders and viscous reagents. Narrow-mouth bottles suit solvents, acids and titrants, and wide-mouth bottles make filling and scooping solids easier. Both are available in clear and amber glass and in plastic, so the mouth type is chosen from the state of the reagent.
Key takeaways
1. The role of a reagent bottle is to store, protect, dispense and identify chemical reagents, keeping them pure and at their stated concentration.
2. Amber (actinic) glass blocks light up to about 500 nm, protecting light-sensitive reagents such as silver nitrate and potassium permanganate from photolysis.
3. Apply the Reagent-Bottle Selection Rule: choose by reagent state, light sensitivity, chemical compatibility and closure.
4. GL45 is the most widely supported laboratory bottle thread, with interchangeable caps and pouring rings, under ISO 4796-1:2016.
5. Reagent-bottle graduations are approximate, with around 10% error, so accurate volumes must be measured with volumetric glassware.
6. Use the ten-step filling and storage checklist and source reagent bottles from the lab glassware and lab chemicals ranges.
About Edu Lab China
Edu Lab China is a manufacturer and exporter of educational and scientific laboratory equipment headquartered in Zhengzhou City Hi-Tech Development Zone, Henan, China, supplying schools, colleges, universities and government institutions across more than 50 countries worldwide. The company states that its products are manufactured under the guidelines of ISO 9001, ISO 13485 and ISO/IEC 17025, with credentials including CE marking, RoHS, REACH and UL and ETL listing. Its range spans lab glassware, reagent bottles, lab chemicals, chemistry, physics and biology lab equipment, and measuring glassware used for chemical storage and handling. For bulk supply, tender documentation and OEM enquiries, contact the Edu Lab China procurement team.
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