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Introduction
Published in Armen S. Casparian, Gergely Sirokman, Ann O. Omollo, Rapid Review of Chemistry for the Life Sciences and Engineering, 2021
Armen S. Casparian, Gergely Sirokman, Ann O. Omollo
It should be remembered that many compounds have chemical names as well as common names. A compound generally has only one correct chemical name but may have more than one common name. For example, the compound Ca(OH)2 has the chemical name calcium hydroxide; it may also be referred to commonly as slaked lime or hydrated lime.
Repair and protection (B) – cathodic protection
Published in Brian Cherry, Green Warren, Corrosion and Protection of Reinforced Concrete, 2021
In order to examine the way in which CP reduces the corrosion rate of the reinforcement it is necessary to examine the corrosion reaction of steel in concrete in a little more detail. It may be assumed that steel immersed in sound concrete is exposed to the liquid that is contained within the pores and capillaries of the hardened cement paste. This is primarily a saturated solution of calcium hydroxide with a pH of about 12.8. The iron oxidation reaction at pH 12.8 may be written: Fes+2H2Ol→FeOH2s+2H+aq+2e−
Applied Chemistry and Physics
Published in Robert A. Burke, Applied Chemistry and Physics, 2020
Calcium hydroxide is a strong corrosive base with a pH of 12.4. It is a skin irritant and inhalation hazard. The TLV is 5 mg/m3 of air. When responders encounter carbides and other water-reactive salts in a spill, they should be careful not to apply water unless absolutely necessary. If rain is forecast, acetylene gas would be generated when the rain contacted the calcium carbide in a spill. Care would have to be taken to cover the material to keep it dry.
Mechanism, prevention and remedy of alkali-pumping in new constructed asphalt pavement
Published in International Journal of Pavement Engineering, 2021
Weixiong Li, Duanyi Wang, Chunlong Xiong, Jiangmiao Yu, Bo Chen, Xianshu Yu
One mechanism is referred to as ‘flowing’ alkali-pumping and is illustrated in Figure 4. During the construction of asphalt pavements, if the flow of alkaline materials from the lower synchronous gravel seal and subsidiary structure becomes uncontrolled due to the insufficient stirring of the asphalt mixture, the alkaline substances can easily dissolve in water. Typically, calcium oxide reacts with water to form water-insoluble calcium hydroxide (Equation (2)). During paving, high temperatures develop, and magnesium oxide reacts with water forming magnesium hydroxide, which induces water solubility (Equation (3)). Then, when the water flowing into the pavement structure in the gravel seal and the subsidiary structure is in contact with the high-temperature mixture, part of the magnesium bicarbonate might decompose to form magnesium carbonate (Equation (4)).
Impact of Portland cement and lime on the stabilization and shear strength characteristics of contaminated clay
Published in Soil and Sediment Contamination: An International Journal, 2023
Mohammad Hajimohammadi, Amir Hamidi
The lime used in this study was a powder of hydrated lime that primarily consisted of calcium hydroxide (Ca(OH)2). It was first passed through a No. 40 sieve (with pore size of 425 μm). The chemical properties of this lime are shown in Table 4. The amounts of lime added to the soil samples were 10%, 20%, and 30% of the oven-dried weight of the soil. These values obtained based on similar UCS with cement stabilized soil. The same contents have also been used by Soltaninejad, Hamidi, and Marandi (2020) for stabilization of kaolinite with lime.
Control of carbon dioxide emission in automobile vehicles using CO2 scrubber
Published in International Journal of Ambient Energy, 2019
V. S. Shaisundaram, M. Chandrasekaran, S. Mohan Raj, R. Muraliraja, T. Vinodkumar
Calcium Hydroxide is an inorganic compound that is obtained when calcium oxide is mixed with water. It is traditionally known as ‘slaked lime’, and is commonly found in the form of crystal or white powder. A suspension of fine calcium hydroxide particle can react with atmospheric carbon dioxide to form calcium carbonate by the following reaction.