Calcium hydroxide
Calcium hydroxide (CAS 1305-62-0; Ca(OH)2; molar mass 74.09 g/mol) is an inorganic base, commonly known as slaked lime or hydrated lime. It is a white, sparingly soluble crystalline powder whose aqueous solution, limewater, is strongly alkaline. Widely used to neutralise acids, adjust pH, soften water and as a calcium source in chemical synthesis, it is supplied by Tech Serve Solutions as an ACS reagent grade material (assay >=95.0%) for laboratory and industrial use.
- Synonyms
- Calcium hydroxideCalcium dihydroxideSlaked limeHydrated limeCalcium(II) hydroxideLimewater (aqueous solution)Caustic limeCa(OH)2
pH adjustment and acid neutralisation
As a strong, economical base, calcium hydroxide is used to neutralise acidic streams and raise pH in water and effluent treatment. Its alkalinity makes it a standard reagent for controlling acidity in laboratory and process settings.
Water and effluent treatment
Calcium hydroxide is employed in water softening, clarification and the precipitation of impurities such as carbonates and heavy metals. It is a long-established reagent for conditioning process and waste water.
Chemical synthesis and calcium source
It serves as a precursor and calcium source in the preparation of other calcium compounds and in general inorganic synthesis. The reagent grade material supports reproducible bench-scale and analytical chemistry.
Analytical and laboratory reagent
Supplied as an ACS reagent grade powder, calcium hydroxide is used in titrations, limewater preparation and routine laboratory work where a defined-purity inorganic base is required.
Carbon dioxide absorption
Calcium hydroxide reacts with carbon dioxide to form calcium carbonate, a property used in gas absorption and in the classic limewater test for CO2. This reaction also underpins its use in setting and hardening applications.
| Molecular weight | 74.09 |
|---|---|
| Linear formula | Ca(OH)2 |
| Assay | ≥95.0% |
| Grade | ACS reagent |
| Density | 2.24 g/mL at 25 °C(lit.) |
| Impurities tested | ≤0.03% insol. in HCl≤0.1% S compounds≤3.0% calcium carbonate |
Hazard statements
- H315Causes skin irritation
- H318Causes serious eye damage
- H335May cause respiratory irritation
Precautionary statements
- P261Avoid breathing dust, fume, gas or vapours
- P280Wear protective gloves, clothing and eye/face protection
- P305IF IN EYES
| Protective equipment | dust mask type N95 (US), Eyeshields, Gloves |
|---|---|
| Water hazard class (WGK, DE) | 1 |
| Hazard codes (EU) | Xi |
| Risk statements (R) | 37/38-41 |
| Safety statements (S) | 26-39 |
| Cation traces | Fe: ≤0.05%K: ≤0.05%Mg: ≤0.5%Na: ≤0.05%Sr: ≤0.05%heavy metals (as Pb): ≤0.003% |
| Anion traces | chloride (Cl-): ≤0.03% |
Hazard information is provided for guidance. Always consult the product Safety Data Sheet (SDS), available on request, before handling.
Documentation
Every batch ships with a Certificate of Analysis covering assay, identity and purity; the grade is confirmed against your enquiry. Safety Data Sheets and technical data sheets are available on request.
Supply & logistics
Samples for technical evaluation; bulk MOQ by grade and packaging. In-stock material ships in 7–10 working days, worldwide, with full export documentation.
What is calcium hydroxide used for?
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Calcium hydroxide is used principally as an inorganic base to neutralise acids and adjust pH, in water and effluent treatment, in chemical synthesis as a calcium source, and as a laboratory reagent for limewater and titrations. It also absorbs carbon dioxide to form calcium carbonate.
What is the CAS number and molecular formula of calcium hydroxide?
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Calcium hydroxide has CAS number 1305-62-0 and the molecular formula Ca(OH)2. Its molecular weight is 74.09 g/mol, the EC number is 215-137-3 and the MDL number is MFCD00010901.
What grade and purity does Tech Serve Solutions supply?
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Tech Serve Solutions supplies calcium hydroxide as an ACS reagent grade material with an assay of >=95.0%. Typical impurity limits include <=3.0% calcium carbonate, <=0.1% sulphur compounds and <=0.03% material insoluble in HCl. We do not represent this item as USP, BP or EP grade unless explicitly agreed in writing.
What are the safety and handling requirements for calcium hydroxide?
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Calcium hydroxide is classified under GHS with signal word Danger and pictograms GHS05 and GHS07. The hazard statements are H315 (causes skin irritation), H318 (causes serious eye damage) and H335 (may cause respiratory irritation). Avoid dust inhalation, wear gloves and eye protection, and use a suitable dust mask (type N95). Refer to the Safety Data Sheet before handling.
How is calcium hydroxide packed, shipped and exported?
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Calcium hydroxide is packed in moisture-resistant containers appropriate to the order quantity, with full labelling and documentation. As a global supplier and exporter, Tech Serve Solutions arranges compliant packaging and shipping, accompanied by a Certificate of Analysis and Safety Data Sheet. Contact us for available pack sizes and lead times.
How do I request a sample or quote?
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To request a sample, current specification or a formal quotation, contact Tech Serve Solutions with the grade, quantity and delivery destination required. We will respond with availability, documentation and export terms.
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