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Methyl Orange Indicator, Pure | pH Indicator Dye for Acid–Base Titrations
$19.00 AUD
Documentation
AuSaMicS Methyl Orange Indicator, Pure (CAT: ASD-633) is a premium-quality azo dye used as a precise pH indicator in analytical chemistry. This batch achieves an exceptionally high dye content of 97.3% by spectrophotometry, well above the standard specification of >95.0%. Known for its distinct, sharp colour transition in acidic environments, Methyl Orange is the standard indicator of choice for acid-base titrations involving strong mineral acids and weak bases.
pH transition range
Transition confirmed by spectrophotometry: λmax 504.2 nm (pH 3.1) and λmax 468.6 nm (pH 4.4)
Product specifications
| Catalog number | ASD-633 |
| CAS number | 547-58-0 |
| Color index | C.I. 13025 (Acid Orange 52) |
| Molecular formula | C₁₄H₁₄N₃NaO₃S |
| Molecular weight | 327.33 g/mol |
| Grade | Laboratory Reagent / Indicator Grade |
| Form | Powder |
| Colour (solid) | Dark orange |
| Solubility | Soluble in water — clear orange solution at 0.1% |
| Dye content | 97.3% (specification: > 95.0%) |
| Loss on drying | 1.39% at 110°C / 1 hr (specification: < 3.0%) |
Key features
High purity — verified spectrophotometric dye content of 97.3%, ensuring potent and reliable indicator solutions
Sharp transition — confirmed pH 3.1 (pink) to 4.4 (orange-yellow) range for precise endpoint detection
Excellent solubility — dissolves completely to form a clear orange solution at 0.1% concentration
Low moisture — 1.39% loss on drying ensures a stable, free-flowing powder with long shelf life
Consistent spectrophotometric performance — absorptivity values within specification at both transition points
Certificate of analysis — batch QC data
| # | Test parameter | Specification | Batch result | Status |
|---|---|---|---|---|
| 1 | Appearance | Orange to yellow powder | Dark Orange Powder | Pass |
| 2 | Solubility (0.1% in distilled water) | Clear solution | Orange Solution | Pass |
| 3 | Transition range | pH 3.1 (Pink) – pH 4.4 (Orange-Yellow) | Passes test | Pass |
| 4a | Absorptivity A(1%/1cm) at pH 3.1 (λmax 504.2 nm) | 1050 – 1150 | 1115 | Pass |
| 4b | Absorptivity A(1%/1cm) at pH 4.4 (λmax 468.6 nm) | 750 – 850 | 813 | Pass |
| 5 | Dye content (by spectrophotometry) | > 95.0% | 97.3% | Pass |
| 6 | Loss on drying (110°C / 1 hr) | < 3.0% | 1.39% | Pass |
Conclusion: The sample COMPLIES with the specifications of the standard.
Applications
Acid-base titrations — strong acids vs weak bases (HCl / Na₂CO₃)
Water analysis — determination of alkalinity in water samples
University and industrial laboratory pH indication
Analytical chemistry research and education
Storage
Store in a tightly closed container in a cool, dry place
Protect from direct light and UV exposure
Stable under recommended storage conditions — refer to label for expiry
Safety information
WARNING — GHS Hazard Classification: H302 Harmful if swallowed · H319 Causes serious eye irritation.
Wear protective gloves and safety goggles. Avoid breathing dust. Do not eat, drink, or smoke when handling. Wash hands thoroughly after use. In case of eye contact, rinse immediately with water for at least 15 minutes and seek medical advice. Full Safety Data Sheet (SDS) available upon request.
Wear protective gloves and safety goggles. Avoid breathing dust. Do not eat, drink, or smoke when handling. Wash hands thoroughly after use. In case of eye contact, rinse immediately with water for at least 15 minutes and seek medical advice. Full Safety Data Sheet (SDS) available upon request.
Intended use
This product is intended for laboratory analytical use only by qualified professionals. Not for use in human or veterinary therapeutic applications, food, feed, or pharmaceutical manufacturing.
Quality & compliance
Manufactured and tested to laboratory reagent grade standards. Full batch-specific Certificate of Analysis (COA), Technical Data Sheet (TDS), and Safety Data Sheet (SDS) available upon request. For bulk quantities or contract pricing, contact sales@ausamics.com.
✓ Reagent grade
✓ COA available
✓ Ships from Australia
✓ 1–3 day delivery