Search results
Results From The WOW.Com Content Network
Lime comes from Old English lim ('sticky substance, birdlime, mortar, cement, gluten'), and is related to Latin limus ('slime, mud, mire'), and linere ('to smear'). [7] Mortar is a mixture with cement and comes from Old French mortier ('builder's mortar, plaster; bowl for mixing') in the late 13th century and Latin mortarium ('mortar'). [7]
A fairly well-defined reaction front can often be observed in thin sections; ahead of the front the concrete is normal, or near normal. Behind the reaction front, the composition and the microstructure of concrete are modified. These changes may vary in type or severity but commonly include: Extensive cracking; Expansion
Whitewash cures through a reaction with carbon dioxide in the atmosphere to form calcium carbonate in the form of calcite, a type of reaction generally known as carbonation or by the more specific term, carbonatation. It is usually applied to exteriors, or interiors of rural dairies because of its mildly antibacterial properties. Whitewash can ...
It also can be the result of chemical reaction; if badly prepared cement-based mortar is applied to maintain the stone in position, free calcium hydroxide may leach out. In the open air the lime reacts with carbon dioxide to form water-insoluble calcium carbonate that might take the form of powdery efflorescence or dripstone -like crusting.
In the lime industry, limestone is a general term for rocks that contain 80% or more of calcium or magnesium carbonate, including marble, chalk, oolite, and marl.Further classification is done by composition as high calcium, argillaceous (clayey), silicious, conglomerate, magnesian, dolomite, and other limestones. [5]
The complete reaction can be derived from the molecular formulas of the reagents and products involved in the reaction. This reaction favors the dissolution of AFt and the formation of AFm. When combined, it is an aggravating factor of the harmful effect of too high temperatures. To minimize DEF, the use of low-alkali cements is also recommended.
If there are cracks or problems in the actual bricks or stone masonry there could be a larger problem that also needs to be addressed. If there is a larger issue, repointing may cause further damage. If a historic structure needs repointing, building owners usually hire an architectural historian or conservator to help pinpoint the issues. [ 2 ]
Calcium carbonate (limestone) Calcium carbonate (limestone) is decomposed by heat to produce calcium oxide (quicklime) and carbon dioxide gas. Then calcium oxide reacts with water to form calcium hydroxide (slaked lime) which is accompanied by the release of heat, a reaction known as exothermic. [1]