He has seen a broad range of cases from fires in domestic properties, to more complex vehicle fires and factory explosions. In fiction, Bernard Cornwell’s 19th Century hero, Richard Sharpe used quicklime that he made by burning oyster shells, to stave off the French army (Sharpe’s Siege). Initially steam came from the straw, but this soon subsided. Should I call the police on then? The tests showed that calcium oxide, when mixed with water, reacts exothermically, and represents a viable ignition source for the straw bedding material on the veranda. CaO(s) + H2O(l) → Ca(OH)2(s) ΔH°rxn = –64.8 kJ/mol How much heat would be liberated when 7.15 g CaO(s) is dropped into a beaker containing 152 g H2O. Apparatus :-50ml measuring cylinder-100ml beaker-electronic balance-thermometer -calcium oxide. the reaction between water and calcium oxide; The slideshow shows an exothermic reaction between sodium hydroxide and hydrochloric acid. The melting component is 2572 °C that's warm sufficient to soften iron (m.p. Calcium oxide and water react in an exothermic reaction: CaO(s) + H2O(l) >>>>> Ca(OH)2(s) Heat of reaction (Rxn) = -64.8 kJ/mol How much heat would be liberated when 7.15 g CaO(s) is dropped into a beaker containing 152 g H2O. I conducted tests to assess if the exothermic reaction of calcium oxide and water could ignite straw. New questions in … Calcium oxide and water Exothermic reaction. Calcite is a softer mineral than some varieties of limestone and can be used to jot down on tougher surfaces. your request as soon as possible. Figure 1: Time – Temperature plot (Channel 1-4 probes were placed in the straw layer above the calcium oxide). Why Is Heat Produced When We Add Water (H2O) To Calcium Oxide (Cao)? The basic operating principle involved in the TES system is a thermochemical reaction involving metal oxides such the calcium oxide (CaO) or magnesium oxide (MgO) and water. this kind of chalk is used usually for development supplies. One of the workers was a smoker, but he stated that he did not smoke inside the buildings. Get answers by asking now. Join Yahoo Answers and get 100 points today. I did not find any smoker’s materials in the area of fire damage, nor did I find any around the other farm buildings. At 17:00, one of the workers noticed smoke coming from the veranda of the building. The piles of white powder (indicated by arrows). When I reviewed the instructions provided with the calcium oxide, I noticed that they failed to specifically mention the risk of fire. CaO(s) + H2O(l) = Ca(OH)2(s) DeltaH= -64.8kJ/mol The aim of this experiment is to find the relationship between the ratio of reactants used and heat given off. Though there were electric lights in the veranda, these were switched off at the time of the fire. A molecule with molecular formula CxHyO yields a parent mass peak of 72 (M+=72)? you will see that including water to a textile at this type of extreme temperature might bring about an astounding explosion from the steam that's produced immediately. Turning CaO right into a soften is a real chore. A layer of clean, dry straw was placed on a metal tray. However, moving the top layer of straw allowed air to reach the blackened straw, and caused it to glow. A layer of clean, dry straw was placed on a metal tray. I noted several piles (approximately 20 cm in diameter) of a white powder amongst the straw in the veranda. Though his career began in the offshore oil and gas pipeline installation industry, Ian joined Hawkins in early 2009, and has been investigating fires and explosions, as well as pedestrian falls, ever since. A layer of straw was placed on top of this; there were four temperature sensors (Channels 1 – 4) inside the top layer of straw. Still have questions? Before Hawkins carried out an examination of the building, the circumstances of the incident were discussed with the two workers who discovered the fire: The fire occurred in a wooden building, which housed laying hens, and had an open-air veranda on one side. The workers said there had neither been recent work on, nor problems with, the fixed wiring in the building. Calcium hydroxide, Ca(OH) 2, forms colorless crystals (resulting in white powder) and is obtained by mixing calcium oxide with water (calcium hydroxide is also called slaked lime). A flaming fire quickly developed. However, the instructions did stipulate that the product must be spread evenly, and that the ground should be wetted prior to treatment. Calcium oxide is most often used in the form of a white powder, made from the thermal decomposition of materials like limestone and seashells. A pile of 500g of calcium oxide was placed on the straw, and then 500ml of water was added. We will also retain your details so we may contact you from time Damage attributable to direct fire attack was limited to the veranda. Quicklime has previously been used as a weapon of war, it is thought to have been one of the components of Greek Fire. Write the formula for the compound that has the atoms and, or groups in the order given: 3 Fe, and two groups made up of 1 As and 4 O.. I went to a Thanksgiving dinner with over 100 guests. A sample of the ore weighing 4.301 g was treated with nitric acid, which dissolved the PbCO3? Dr Ian Tatner is a Chartered Engineer (CEng) with a PhD in Corrosion Fatigue of Stainless Steel. I removed the top layer of straw and saw that the straw underneath it was blackened. The temperature of Channel 1, Channel 3 and Channel 4 increased rapidly once water was added to the calcium oxide. It can be used to disinfect and sanitize, because it creates a dry environment where bacteria will not thrive. Channel 3 and Channel 4 reached a maximum of approximately 100°C and then plateaued, while Channel 1 continued to rise until it reached approximately 370°C, about nine minutes after water was added. If the calcium oxide had been spread evenly onto a pre-wetted surface, the exothermic reaction would have occurred rapidly, and heat would have been lost to the surroundings. Adding water to calcium oxide is exothermic reaction 2 See answers kalpanasanjaygupta kalpanasanjaygupta Answer: Because in this reaction hydrogen which contain heat is envolved. This reduced the amount of heat lost to the surroundings, and instead provided a readily ignitable material. Ian has also investigated numerous pedestrian falls in both public and private buildings. A pile of 500g of calcium oxide was placed on the straw, and then 500ml of water was added. • The major use of quicklime is in the basic oxygen steelmaking (BOS) process. Its reaction with some other substance is endothermic or exothermic like when calcium oxide reacts with water large amount of heat is evolved. that's a mineral talked approximately as calcite and is composed of CaCO3.