C2.1.1 Structure and bonding a) Compounds are substances in which atoms of two or more elements are chemically combined. b) Chemical bonding involves either transferring or sharing electrons in the highest occupied energy levels (shells) of atoms in order to achieve the electronic structure of a noble gas. c) When atoms form chemical bonds by transferring electrons‚ they form ions. Atoms that lose electrons become positively charged ions. Atoms that gain electrons become negatively charged
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Espana Street‚ Manila 1008 Date Submitted: September 13‚ 2012 ------------------------------------------------- Abstract Carboxylic acid derivatives namely‚ acyl halides‚ acid anhydrides‚ esters and amides were classified through different reactivity tests. The samples used were acetyl chloride for acyl halide group‚ acetic anhydride for acid anhydride group‚ ethyl acetate for ester group‚ acetamide and benzamide for amide group. These derivatives were identified through the mechanism of hydrolysis
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having been demonstrated in the 19th century. Hypertension occurred due to a decrease in intracellular free magnesium as hypomagnesaemia increased vascular tone and reactivity which lead to the rise in total peripheral resistance. At a cellular level‚ rise in the intracellular calcium content is associated with the increased tone and reactivity. It also decreased activation of calcium channels‚ which may enhance the diffusion of calcium current into cells‚ decrease calcium efflux from cells‚ increase cellular
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Children’s heavy dependency on screens has caused major damage to their development (Muppalla). In fact‚ three cognitive aspects of a child’s brain are damaged due to this (Muppalla). Additionally‚ screen time negatively impacts a child’s language development‚ making it difficult for them to communicate (Muppalla). Lastly‚ social-emotional development is damaged‚ creating a low emotional intelligence (Muppalla). In turn‚ educating guardians would be beneficial to their child’s growth and overall
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climatic factors such as rainfall‚ temperature and relative humidity during the dengue fever epidemic in the year 2003. Blood samples were collected from 1550 patients experiencing a febrile illness clinically consistent with dengue infection. Serological confirmation of Dengue Infection was done using Dengue Duo IgM and IgG Rapid Strip test (Pan Bio‚ Australia)‚ which detected dengue-specific antibodies. Monthly data of total rainfall‚ temperature and relative humidity for the year 2003 was obtained from
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even if the melting point temperatures are in the same range with biomass fuels. Coal or peat is co-fired with biomass in many multi-fuel fired boilers. The woody biomass ashes are in general much more reactive than the ashes of fossil fuels. Lower reactivity of coal and peat ashes is connected to a composition with mainly quartz and various silicate-based minerals‚ like aluminium silicates‚ calcium silicates and alkali silicates‚ and iron oxides. Calcium and al kali in these minerals are not in free
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describes the cause of the actual trauma itself. Requiring the person to be exposed to or threatened by death‚ injury or sexual assault. This criterion also states that the exposure can be “directly or indirectly witnessed”‚ meaning that it happens to a relative or friend who experienced the trauma. Criterion B is labeled “Intrusion Symptoms”‚ the reexperiencing of the traumatic
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Q3: Describe and discuss the durability properties of hardened concrete. Durability is the ability of concrete to handle deterioration from the surroundings or at the service in which it is placed. The most important things that cause rust could be divided into two chemical and physical causes. The Chemical durability complications are disturbed with countless formulae reactions of cement-aggregate. On the other hand In the physical durability aspect problems are concerned from the aggregates
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The purpose of this experiment was used to identify the chemical changes a substance undergoes by knowing some of its chemical properties like (Change in color‚ producing bubbles and gas‚ precipitation‚ conductivity). The aim of today’s lab was to help us identify different households and their components‚ they contained whether they were acid/ base‚ because most of the households are based on those solutions like (i.e. Acetic acid = Vinegar = CH3COOH can be used in cooking) or bases solutions
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concentration is 100% because the more the substrate‚ the faster the enzyme can bind to it. Based on the data above‚ all four hypotheses were proven correct. Based on the graph and data table‚ the optimal temperature for sucrase was 37°C because it had a reactivity score of 4‚ meaning it was very reactive. For the pH test‚ based on the graph and data table‚ the optimal pH was in fact ranged from 3-7. This means that any pH from 3-7‚ gives the highest rate of reaction to sucrase. The denatured test was proven
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