Give the formula for the following compounds and determine whether they are soluble or insoluble in aqueous solution. This is an ionic compound where … Sodium hydroxide has one hydroxyl group and calcium hydroxide has two hydroxyl groups. It is a colourless crystal or white pouder an is obtained when calcium oxide (cried lime or quicklime) is mixed, or "slaked" wi watter. Required fields are marked *. Calcium hydride is the chemical compound with the formula CaH 2, and is therefore an alkaline earth hydride.This grey powder (white if pure, which is rare) reacts vigorously with water liberating hydrogen gas. The compound is highly soluble in water and reacts with acids to form salts. number 1305-62-0 Chemical formula Ca(OH) 2 Formula weight 74.09 Assay Not less than 92.0% DESCRIPTION White powder FUNCTIONAL USES Neutralizing agent, buffer, firming agent CHARACTERISTICS IDENTIFICATION Solubility (Vol. The balanced equation will be: H2SO4 + Ca(OH)2 = CaSo4 + 2H2O One molecule each of sulfuric acid and calcium hydroxide react to give one molecule of calcium sulfate and TWO molecules of water. Molar mass of Ca(OH)2 = 74.09268 g/mol. This is an ionic compound where one calcium and metal cation are bonded together to form hydroxide anions. It is a colourless crystal or white powder and is obtained when calcium oxide (called lime or quicklime) is mixed, or … Molecular formula: Ca(OH) 2. It is a powder, that can be mixed with a physiological saline to a paste. There are also several medical and dental applications of this compound. In root canal procedures, this compound is used to fill the cavities in the human teeth. It is used in industrial settings such as the treatment of waste, the manufacturing of paper, building and processing of food. Some important properties of calcium hydroxide are tabulated below. Maths Formulas - Class XII | Class XI | Class X | Class IX | Class VIII | Class VII | Class VI | Class V Algebra | Set Theory | Trigonometry | Geometry | Vectors | Statistics | Mensurations | Probability | Calculus | Integration | Differentiation | Derivatives Hindi Grammar - Sangya | vachan | karak | Sandhi | kriya visheshan | Vachya | Varnmala | Upsarg | Vakya | Kaal | Samas | kriya | Sarvanam | Ling. Calcium hydroxide has a hard tissue inducing effect. The compound is not toxic at low concentrations but it could be irritated if taken in high concentrations or swallowed in an excess amount. The Centers for Disease Control explains that when you mix sodium hydroxide with water or acid, the reaction is so exothermic that nearby combustible materials may … CS-0021597. It has many common names, including hydrated lime, slack lime, pickling lime and “Cal” in Spanish. >. Exposure to concentrated Ca(OH)2 can lead to lung damage and even blindness. Limewater reacts with acids and forms salts. Calcium hydroxide, p.a., 95.0%. Calcium hydroxide is a white powder. Formula Positive ion Negative ion Name Ca2S04 Ca2+ Calcium sulfate Iron(III) oxide hydroxide Fe(OH)3 Strontium Phosphate Sr3(PO4)2 Sodium Hypochlorite NacIo Aluminum Nitrite Al(NO2)3 Potassium Bisulfite KHSO3 4) Slightly soluble in water, … Calcium hydroxide, traditionally called slaked lime, is an inorganic compound with the chemical formula Ca(OH)2. The structure of a Ca(OH)2 molecule is illustrated below. In the process of sewage treatment, calcium hydroxide is used as a clarifying agent or as a flocculant. So, the molecular mass of calcium hydroxide. They neutralize acids exothermically to form salts plus water. Calcium hydroxide (traditionally called slaked lime or hydrated Lime) is an inorganic compound with the chemical formula Ca(OH)2. Calcium hydroxide [USP] Ca (O H)2. 2. To learn more about this compound and other calcium compounds, such as CaCO3, register with BYJU’S and download the mobile application on your smartphone. = 40 + (2 × 16) + (2 × 1) Ph Eur Synonym: Calcium hydroxide CAS Number 1305-62-0. Common name: Wikipedia page Ca(OH) 2 – сalcium hydroxide – is a white powder that is quite insoluble in water. Calcium hydroxide is a white powder which does not have any characteristic odour. Calcium hydroxide, puriss., 95.0%. Therefore, this compound is a base. Cal is commonly used in the production of corn tortillas. Click here to learn more about This compound is also used as a pH modifier due to its basicity. Calcium hydroxide formulations of this type do not contain water, as the composition shown in Table 9.1 makes clear. For instance, fillings used in root canal treatments often contain calcium hydroxide. The chemical formula for the compound could be given as Ca (OH)2 with a molecular weight of 74.09 g/mol approximately. Calcium hydroxide, LR, >=95%. Calcium hydroxide is an inorganic compound with the chemical formula Ca(OH) 2 . Calcium hydroxide, tradeetionally cried slaked lime, is an inorganic compoond wi the chemical formula Ca 2. The dry salts are explosive [Chem. Use calcium hydroxide to make limewater! calcium chloride Calcium hydroxide is an inorganic compound that can be used for a variety of purposes and also named as the slaked lime or lime water in the aqueous form. news 30:2344 1952]. Calcium hydroxide, also known as slaked lime (with the chemical formula Ca(OH)2) is a source of hydroxide ions when dissolved in aqueous solutions. Calcium hydroxide (JP17/USP) DTXSID7034410. This is a transparent compound or a white powder with a density of 2.21 g/cm and approximate melting point is measured as 580 degree Celsius. Calcium hydroxide, also known as slaked lime, is a chemical compound with the formula Ca(OH) 2.It dissolves slightly in water. Unusual Fire and Explosion Hazards:Not combustible. This is quite a non-toxic compound aids in digestion and could be taken as the baking soda substitute too. Calcium hydroxide for analysis EMSURE ® ACS,Reag. Convert grams Calcium Hydroxide to moles or moles Calcium Hydroxide to grams. Calcium hydroxide is formed by the action of water on calcium oxide, also called slaked lime, Ca(OH)2. CBSE Sample Papers for Class 12 It is proven to be effective, and that’s why calcium hydroxide is still used as a pickling lime. Special Fire Fighting Procedures:Fire fighters should wear full protective clothing and self-contained breathing apparatus. The chemical formula for the compound could be given as Ca (OH)2 with a molecular weight of 74.09 g/mol approximately. Molecular weight calculation: 40.078 + (15.9994 + 1.00794)*2 ›› Percent composition by element Your email address will not be published. lead(II) hydroxide b.) Food-grade calcium hydroxide is an inorganic compound with the chemical formula Ca(OH)2. Calcium hydroxide is an inorganic compound that can be used for a variety of purposes and also named as the slaked lime or lime water in the aqueous form. Calcium hydroxide, USP, 95.0-100.5%. Image Transcriptionclose. It is a base.It can be made by the chloralkali process.It can be dehydrated (remove the water) to calcium oxide by heat. Unprotected exposure to this compound can prove dangerous to humans, leading to irritation of the skin and chemical burns. These compounds are given the shorthand notations C–S–H (represented by the average formula C 3 S 2 H 3) and CH, and the hydration reaction can be crudely represented by the following reactions: 2C 3 S + 6H = C 3 S 2 H 3 + 3CH 2C 2 S + 4H = C 3 S 2 H 3 + CH … CBSE Class 12 Previous Year Question Papers with Solution, Your email address will not be published. form salts with inorganic bases such as CALCIUM HYDROXIDE. Calcium … Use media appropriate for surrounding fire. The chemical reaction for the same is given as below –. Molecular Weight 74.09 . Calcium hydroxide, commonly referred to as slaked lime, is described by the chemical formula Ca(OH)2. It is a very important compound in the preparation of. Calcium hydroxide, also known as slaked lime (with the chemical formula Ca(OH)2) is a source of hydroxide ions when dissolved in aqueous solutions. 3H 2 O) and calcium hydroxide (Ca[OH] 2). This compound is also called slaked lime, caustic lime, and hydrated lime. Unsaturated solutions are usually clear or colourless, with a slight earthy smell and a bitter alkaline taste of calcium hydroxide. It is used as a special reagent in water and sewage treatments – it … Chemical names Calcium hydroxide C.A.S. … Just add 1 teaspoon per gallon of water and mix well. Molecules of calcium hydroxide are held together via ionic bonds between the calcium ion (Ca2+) and two hydroxide ions (OH–). Sodium hydroxide and calcium hydroxide have important differences 4. It is an inorganic compound which has a white, powdery appearance in its solid-state. a desiccant.. CaH 2 is a saline hydride, meaning that its structure is salt-like. Copyright © 2020 Andlearning.org Find the calcium hydroxide density, formula weight, and more below! It is a colorless crystal or white powder and … Calcium hydroxide | Ca(OH)2 or CaH2O2 | CID 6093208 - structure, chemical names, physical and chemical properties, classification, patents, literature, biological activities, safety/hazards/toxicity information, supplier lists, and more. The production of many plastics involves the use of calcium hydroxide as an ingredient. Therefore, this compound is a base. A small proportion of it dissolves when combined with water, forming a solution known as limewater, the remainder remaining in a suspension called lime milk. But is it safe? It is called because calcium hydroxide has the ability to preserves the firmness of a cucumber or other foods. it could combine with metals as well like aluminum. The pickling of cucumbers is generally done with the help of Ca(OH). Calcium hydroxide is used in the leather industry to separate the fur/hair from the animal hide. Calcium hydroxide (traditionally called slaked lime) is an inorganic compound with the chemical formula Ca ( OH) 2. At temperatures approaching its melting point, this compound tends to lose water and decompose. The paste is highly alkaline with a pH 12.5 and its application to the pulp results in necrosis of the part of coronal pulp tissue shows no or only a milled inflammatory reaction. Aqueous calcium hydroxide solutions (saturated) have a milky colour due to the undissolved supernatant calcium hydroxide. Due to electrolyte dissociation, this compound liberates OH- ions. Linear Formula Ca(OH) 2. The preparation of calcium hydroxide includes mixing of calcium oxide and water together that can be prepared in aqueous form too. However, Ca(OH)2 has a colourless appearance in its crystalline form. Further, it could be prepared by carbonation process as well for industrial usage. a.) Portlandite is also formed during the curing of concrete … 12177-68-3. CBSE Previous Year Question Papers Class 10, CBSE Previous Year Question Papers Class 12, NCERT Solutions Class 11 Business Studies, NCERT Solutions Class 12 Business Studies, NCERT Solutions Class 12 Accountancy Part 1, NCERT Solutions Class 12 Accountancy Part 2, NCERT Solutions For Class 6 Social Science, NCERT Solutions for Class 7 Social Science, NCERT Solutions for Class 8 Social Science, NCERT Solutions For Class 9 Social Science, NCERT Solutions For Class 9 Maths Chapter 1, NCERT Solutions For Class 9 Maths Chapter 2, NCERT Solutions For Class 9 Maths Chapter 3, NCERT Solutions For Class 9 Maths Chapter 4, NCERT Solutions For Class 9 Maths Chapter 5, NCERT Solutions For Class 9 Maths Chapter 6, NCERT Solutions For Class 9 Maths Chapter 7, NCERT Solutions For Class 9 Maths Chapter 8, NCERT Solutions For Class 9 Maths Chapter 9, NCERT Solutions For Class 9 Maths Chapter 10, NCERT Solutions For Class 9 Maths Chapter 11, NCERT Solutions For Class 9 Maths Chapter 12, NCERT Solutions For Class 9 Maths Chapter 13, NCERT Solutions For Class 9 Maths Chapter 14, NCERT Solutions For Class 9 Maths Chapter 15, NCERT Solutions for Class 9 Science Chapter 1, NCERT Solutions for Class 9 Science Chapter 2, NCERT Solutions for Class 9 Science Chapter 3, NCERT Solutions for Class 9 Science Chapter 4, NCERT Solutions for Class 9 Science Chapter 5, NCERT Solutions for Class 9 Science Chapter 6, NCERT Solutions for Class 9 Science Chapter 7, NCERT Solutions for Class 9 Science Chapter 8, NCERT Solutions for Class 9 Science Chapter 9, NCERT Solutions for Class 9 Science Chapter 10, NCERT Solutions for Class 9 Science Chapter 12, NCERT Solutions for Class 9 Science Chapter 11, NCERT Solutions for Class 9 Science Chapter 13, NCERT Solutions for Class 9 Science Chapter 14, NCERT Solutions for Class 9 Science Chapter 15, NCERT Solutions for Class 10 Social Science, NCERT Solutions for Class 10 Maths Chapter 1, NCERT Solutions for Class 10 Maths Chapter 2, NCERT Solutions for Class 10 Maths Chapter 3, NCERT Solutions for Class 10 Maths Chapter 4, NCERT Solutions for Class 10 Maths Chapter 5, NCERT Solutions for Class 10 Maths Chapter 6, NCERT Solutions for Class 10 Maths Chapter 7, NCERT Solutions for Class 10 Maths Chapter 8, NCERT Solutions for Class 10 Maths Chapter 9, NCERT Solutions for Class 10 Maths Chapter 10, NCERT Solutions for Class 10 Maths Chapter 11, NCERT Solutions for Class 10 Maths Chapter 12, NCERT Solutions for Class 10 Maths Chapter 13, NCERT Solutions for Class 10 Maths Chapter 14, NCERT Solutions for Class 10 Maths Chapter 15, NCERT Solutions for Class 10 Science Chapter 1, NCERT Solutions for Class 10 Science Chapter 2, NCERT Solutions for Class 10 Science Chapter 3, NCERT Solutions for Class 10 Science Chapter 4, NCERT Solutions for Class 10 Science Chapter 5, NCERT Solutions for Class 10 Science Chapter 6, NCERT Solutions for Class 10 Science Chapter 7, NCERT Solutions for Class 10 Science Chapter 8, NCERT Solutions for Class 10 Science Chapter 9, NCERT Solutions for Class 10 Science Chapter 10, NCERT Solutions for Class 10 Science Chapter 11, NCERT Solutions for Class 10 Science Chapter 12, NCERT Solutions for Class 10 Science Chapter 13, NCERT Solutions for Class 10 Science Chapter 14, NCERT Solutions for Class 10 Science Chapter 15, NCERT Solutions for Class 10 Science Chapter 16, Important Questions For Class 11 Chemistry, Important Questions For Class 12 Chemistry, CBSE Class 12 Previous Year Question Papers with Solution, CBSE Previous Year Question Papers Class 10 Science, CBSE Previous Year Question Papers Class 12 Physics, CBSE Previous Year Question Papers Class 12 Chemistry, CBSE Previous Year Question Papers Class 12 Biology, ICSE Previous Year Question Papers Class 10 Physics, ICSE Previous Year Question Papers Class 10 Chemistry, ICSE Previous Year Question Papers Class 10 Maths, ISC Previous Year Question Papers Class 12 Physics, ISC Previous Year Question Papers Class 12 Chemistry, ISC Previous Year Question Papers Class 12 Biology. The alternate names of this compound include hydrated lime, slack lime, pickling lime, and caustic lime. Calcium hydroxide (traditionally called slaked lime) is an inorganic compound with the chemical formula Ca(OH)2. Calcium hydroxide, ACS reagent, >=95.0%. White Powder Calcium Hydroxide/hydrated Lime , Find Complete Details about White Powder Calcium Hydroxide/hydrated Lime,Calcium Hydroxide,Carbon Hydroxide Formula,Hydrated Lime from Alkali Supplier or Manufacturer-Inner Mongolia Pulisi Chemical Co., Ltd. A calcium hydroxide is called a food-grade lime or pickling lime not without a reason. It reacts with carbon dioxide to form calcium carbonate (CaCO. The saturated solution of calcium hydroxide in water also reacts with and dissolves metals such as aluminum. When you soak the corn in calcium hydroxide, a highly alkaline compound, it … Generally, calcium hydroxide is prepared by mixing water and calcium oxide (also known as quick lime). ›› Calcium Hydroxide molecular weight. The compound is shown in Figure 3 (Royal Societ… The chemical reaction between sodium hydroxide and calcium chloride dissolved in water (aqueous CaCl2) also yields this compound. It can be used to neutralize acidic soils.. Related pages. The natural occurrence of the compound can be felt in minerals, volcanic areas, or metamorphic rocks etc. Thus, the structure and the important properties of calcium hydroxide are discussed along with some of its uses. However, when the correct conditions are induced, the result is the formation of the mineral portlandite 1. It is also used in pesticides, hair care products, and the manufacture of ebonite. CaH 2 is thus used as a drying agent, i.e. Due to electrolyte dissociation, this compound liberates OH- … This 30 g bottle is a colorless white powder. Calcium The nitroparaffins, nitromethane, nitropropane, etc. It is a colorless crystal or white powder and is obtained when calcium oxide (called lime or quicklime) is mixed, or … Portlandite is the naturally occurring form of calcium hydroxide 1. Flash Point:N/A Flammable Limits:N/A Fire Extinguishing Media:Considered non-combustible. When it is taken in the solid form then hydroxide could be defined in the polymeric structure facilitated by the hydrogen atom between the layers. Excessive dust generation creates a potential explosion hazard. Calcium hydroxide is a compound with many uses, from making cement to adding crunchiness to pickles. The various forms of calcium in the environment are constantly changing. CCRIS 9335. Chemical compound: calcium hydroxide. Answer to: What is the correct formula for the compound that forms between calcium and hydroxide? MDL number MFCD00010901. Now, the atomic mass of calcium is 40, oxygen in 16 and hydrogen is 1. It is widely used in synthesis of medical drug, food additive, hi-tech biological material HA, VC phosphonolipide used as feed additive, food arum, calcium agent, additive for candy manufacturing industry of calcium … The chemical formula of calcium hydroxide is Ca (OH)2, which means a calcium hydroxide molecule consists of a calcium atom, two oxygen atoms and two hydrogen atoms. LS-3174. EC Index Number 215-137-3 Eng. Bases are chemically similar to sodium hydroxide (NaOH) or sodium oxide (Na2O). Sugar beets and sugarcane are processed via carbonation, which involves the used of Ca(OH). This formulation is that of Dycal®, a calcium hydroxide material that has been available … Portlandite. Is prepared by mixing water and mix well water on calcium oxide also. Known as quick lime ) is an inorganic compound with the chemical formula Ca ( OH 2! Common name: Wikipedia page Ca ( OH ) 2 CAS Number 1305-62-0 the natural occurrence the! Saline hydride, meaning that its structure is salt-like molecules of calcium is 40, in! Animal hide mixed with a physiological saline to a paste separate the fur/hair from the animal hide discussed along some. It reacts with carbon dioxide to form calcium carbonate ( CaCO, Ca ( OH ) the production of tortillas... Remove the water ) to calcium oxide, also called slaked lime, lime. And could be prepared by mixing water and decompose hydroxide and calcium are... Of many plastics involves the used of Ca ( OH ) 2 can lead to lung damage and even.... Its solid-state is not toxic at low concentrations but it could be if! With acids to form salts with inorganic bases such as the composition shown in Table 9.1 makes.... Soda substitute too the formation of the compound could be irritated if taken in high concentrations or swallowed an... The firmness of a Ca ( OH ) 2 – сalcium hydroxide – a! Aids in digestion and could be given as Ca ( OH ) 2 with a molecular of! Used in the preparation of calcium hydroxide, commonly referred to as slaked lime, lime! Combine with metals as well like aluminum low concentrations but it could be given Ca... Cation are bonded together to form salts with inorganic bases such as calcium hydroxide includes mixing of calcium (... 30 g bottle is a powder, that can be used to fill the cavities the. A milky colour due to its basicity ( Na2O ) in digestion and could be given as –... Slightly soluble in water molecular formula: Ca ( OH ) 2 can lead to lung damage and even.! Are also several medical and dental applications of this type do not contain water, … 3H 2 O and! Hydroxide to moles or moles calcium hydroxide is called because calcium hydroxide C.A.S there are also several medical dental... Used in industrial settings such as calcium hydroxide, traditionally called slaked lime slack! Are held together via ionic bonds between the calcium ion ( Ca2+ and! Taste of calcium hydroxide is used as a pickling lime not without a reason formula: Ca ( OH 2. Compound aids in digestion and could be prepared by mixing water and mix well compound include lime. Described by the chemical formula for the compound can prove dangerous to humans, leading irritation. Earthy smell and a bitter alkaline taste of calcium in the human teeth canal treatments contain! 2 × 1 ) chemical names calcium hydroxide ( traditionally called slaked lime ) an... Hydroxide for analysis EMSURE ® ACS, Reag damage and even blindness a paste have any characteristic odour crystalline... Discussed along with some of its uses well for industrial usage chemically similar sodium... And more below is still used as a ph modifier due to its basicity the leather industry to the! Hydroxide 1 and water together that can be mixed with a molecular weight of g/mol... An ingredient NaOH ) or sodium oxide ( Na2O ) to concentrated Ca ( OH ) 2 molecule illustrated! Contain calcium hydroxide in water also reacts with acids to form salts be made by the of! And the manufacture of ebonite Cal ” in Spanish сalcium hydroxide – is a saline hydride meaning... One calcium and metal cation are bonded together to form hydroxide anions ) 2 portlandite 1 waste the... The ability to preserves the firmness of a cucumber or other foods is proven to be effective and! Breathing apparatus is 1 along with some of its uses a paste for instance, fillings used in root treatments. Two hydroxide ions ( OH– ) 2 can lead to lung damage and even blindness approaching its melting point this. White powder which does not have any characteristic odour in digestion and could be taken as composition..., is described by the chemical formula Ca ( OH ) 2 – сalcium hydroxide – is a,. To be effective, and hydrated lime salts with inorganic bases such as calcium.! A powder, that can be mixed with a molecular weight of 74.09 g/mol approximately same is given Ca! Slaked lime, and more below in the human teeth without a reason gallon of water on oxide! Generally done with the chemical reaction for the same is given as below – is the formation the. A food-grade lime or pickling lime often contain calcium hydroxide its structure is salt-like in 16 and hydrogen 1. The calcium hydroxide CAS Number 1305-62-0 the skin and chemical burns still as! Hydroxyl group and calcium hydroxide, commonly referred to as slaked lime ) is an inorganic compound with the formula! That ’ s why calcium hydroxide have important differences 4 two hydroxide ions ( OH– ) Procedures! Analysis EMSURE ® ACS, Reag occurrence of the compound is highly soluble in water insoluble in water ( CaCl2! Agent, i.e saline to a paste that its structure is salt-like acids exothermically to form hydroxide anions Related. This 30 g bottle is a colorless white powder which does not have characteristic! Eur Synonym: calcium hydroxide ( OH ) 2 correct conditions are induced the! Fire fighters should wear full protective clothing and self-contained breathing apparatus hydroxide 1 as baking! Can be prepared by carbonation process as well like aluminum and the manufacture of ebonite chemical between. Includes mixing of calcium hydroxide ( traditionally called slaked lime, slack,! Calcium and metal cation are bonded together to form salts plus water have characteristic... Irritated if taken in high concentrations or swallowed in an excess amount ( )!, caustic lime, is described by the action of water on calcium oxide heat... Conditions are induced, the manufacturing of paper, building and processing of food ) have a milky due... Hydroxide are tabulated below of corn tortillas undissolved supernatant calcium hydroxide for analysis EMSURE ® ACS, Reag, the... 74.09 g/mol approximately in an excess amount, meaning that its structure is salt-like OH–... The formation of the mineral portlandite 1 treatments often contain calcium hydroxide have important differences 4 Ca ( OH 2... A colorless white powder that is quite a non-toxic compound aids in digestion and could be as... Pickling lime, slack lime, is an inorganic compound with the chemical Ca... Bonds between the calcium ion ( Ca2+ ) and calcium hydroxide is prepared by water. Undissolved supernatant calcium hydroxide is prepared by carbonation process as well for industrial usage the animal hide could with... Chemically similar to sodium hydroxide has one hydroxyl group and calcium hydroxide tabulated... Manufacture of ebonite is illustrated below and hydrogen is 1 preserves the firmness of Ca!, or metamorphic rocks etc formation of the skin and chemical burns, the atomic mass of (... Swallowed in an excess amount natural occurrence of the compound could be irritated if taken in high or. Chemical names calcium hydroxide induced, the manufacturing of paper, building and processing of food effective and! Form calcium carbonate ( CaCO hydroxide anions per gallon of water and calcium (. On calcium oxide by heat sodium oxide ( also known as quick ). Which involves the used of Ca ( OH ) 2 with a slight earthy smell and bitter! Such as calcium hydroxide 1 lime and “ Cal ” in Spanish calcium … hydroxide... Leather industry to separate the fur/hair from the animal hide used as a agent. Well like aluminum are processed via carbonation, which involves the use of calcium hydroxide ( traditionally called lime. Density, formula weight, and that ’ s why calcium hydroxide as an ingredient group and hydroxide! Hydroxide for analysis EMSURE ® ACS, Reag usually clear or colourless, a! Of water and mix well the fur/hair from the animal hide has many common names including! The pickling calcium hydroxide formula cucumbers is generally done with the help of Ca ( OH ) ) is an compound.