Reactions which release energy are described as exothermic and those which absorb energy are endothermic. The energy released in chemical reactions was previously stored as chemical potential energy in the reactants; this stored energy is called enthalpy. The aim of this practical is to observe and classify chemical processes as endothermic or exothermic‚ based on the changes in temperature measured and the observations made. If a chemical reaction produces products with more chemical potential
Premium Thermodynamics Chemical reaction Energy
THE s-BLOCK ELEMENTS 291 UNIT 10 THE s -BLOCK ELEMENTS The first element of alkali and alkaline earth metals differs in many respects from the other members of the group After studying this unit‚ you will be able to • describe the general characteristics of the alkali metals and their compounds; • explain the general characteristics of the alkaline earth metals and their compounds; • describe the manufacture‚ properties and uses of industrially important sodium and calcium
Premium Lithium Calcium Metal
IONIC COMPOUNDS In chemistry‚ an ionic compound is a chemical compound in which ions are held together in a lattice structure by ionic bonds. Usually‚ the positively charged portion consists of metal cations and the negatively charged portion is an anion or polyatomic ion. Ions in ionic compounds are held together by the electrostatic forcesbetween oppositely charged bodies. Ionic compounds have high melting and boiling points‚ and they are hard and very brittle. Ions can be single atoms‚ as the sodium and chlorine in
Premium Ion Atom Chemical bond
the formula Ccal = -(ΔHwater * nLR) / ΔT (eq 1) where ΔHwater is the enthalpy change of water. This is equal to -55.81 kJ/mol. nLR is the number of moles of the limiting reactant‚ and ΔT is the change in temperature associated with the reaction. The Ccal obtained was later used to determine the experimental values of the enthalpy change of the reactions (ΔHrxn). Six other reactions were also used to determine its enthalpy change. The reactions are: Neutralization: a. Ammonia and hydrochloric
Premium Thermodynamics Chemical reaction Sulfuric acid
materials using cheesecloth. A clean‚ cotton cloth was then subjected to a series of procedures from pretreatment and mordanting down to dyeing with the rnangosteen extract. Alum and copper sulfate were used as mordants. Results revealed that the mangosteen extract was stabilized by both mordants‚ but copper sulfate was a better fixing agent than alum‚ because it intensified the color of the extract. It can be concluded that the mangosteen husk extract can effectively be used as an alternative‚ environment-friendly
Premium Alum Aluminium Dye
materials using cheesecloth. A clean‚ cotton cloth was then subjected to a series of procedures from pretreatment and mordanting down to dyeing with the rnangosteen extract. Alum and copper sulfate were used as mordants. Results revealed that the mangosteen extract was stabilized by both mordants‚ but copper sulfate was a better fixing agent than alum‚ because it intensified the color of
Premium Alum Garcinia Aluminium
2014 Purpose: To determine the identity of an unknown hydrated salt calculating the percent water loss after heating and also to determine the empirical formula of magnesium oxide. Results: Table 1: Determination of the mass of waters of hydration of an unknown hydrated compound. Hydrated Compound code: C-14 Mass (g) Crucible + Lid 30.581g Crucible + Lid + Hydrated compound 31.590g Hydrated Compound 1.004g Crucible + Lid + contents (after 1st heating) 31.122g Crucible + Lid + contents
Premium Chemistry Molecule Water
could measure the density of atoms with crude experiments. The second part of the experiment dealt with Solubility of large ions and their Hydration enthalpy. Hydration enthalpy is the enthalpy change when 1 mole of an ionic substance dissolves in a solution to give a solution of infinite dilution. (Jim Clark‚ 2010). (Jonathan Hopton‚ 2011) Hydration Enthalpy decreases (gets less negative) down a group‚ the Solubility of the group 2 metals also decreases down the group. Methods The method was followed
Premium Chemistry Periodic table Chemical element
FINAL PROJECT 1 Final Project Assignment Shawn Ovington XACC/280 Sheila Sullivan FINAL PROJECT 2 Keeping good records is a key in any good business and it helps companies find key areas where they feel they can improve. Coke and Pepsi are two large named soda distributers that have
Premium Balance sheet Generally Accepted Accounting Principles Asset
notation of the following: O‚ Na‚ Na+‚ Al‚ Cl- and Co (Total 6 Marks) Write the electronic configuration in box notation of the following: N‚ Si and Ni (Total 3 Marks) 3. Write the electronic configuration in box notation of chromium and copper. Suggest reasons for the apparently anomalous arrangement of electrons in their atoms. (Total 4 Marks) 4. The following table shows the first three ionization energies (in kJ mol-1) of elements in the SAME group of the Periodic Table. Element
Premium Sodium hydroxide Enthalpy Hydrochloric acid