Identifying an Ionic Compound. Objectives: To learn and test for metal ions and non-metal ions and then apply them to discover the identity of an unknown ionically bonded substance

Identifying an Ionic Compound- Introduction Ionic compounds are defined as being compounds where two or more ions (an atom or group of atoms with an overall electrical charge) are held next to each other by electrical attraction. One of the ions has a positive charge - called a "cation", and the other has a negative charge - called "anion". Cations are usually metal atoms and anions are either nonmetal or polyatomic ions (ions with more than one atom). Usually, when we have ionic compounds, they form large crystals that you can see with the naked eye. Table salt is one of this- if you look at a crystal of salt, you can see that it has in irregular cube shape. This is because salt likes to stack in little cube-shaped blocks. When forming salt, Na readily loses an electron and Cl readily gains an electrons so both can become stable. Heat is added in the reaction so Na burns brightly in CL gas and a white solid forms on the sides of the container. This solid is salt, or sodium chloride. When the chlorine atom gained an electron, the atoms arrange themselves in a lattice. The force of attraction between a cation and anion is a very strong bond called an "ionic bond". This is an electrostatic attraction. An ionic bond happens between a metal and a nonmetal. Properties of salts: 0. All ionic compounds form crystals. 0. Ionic compounds tend to have high melting and boiling

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Temp labreport

How Temperature of HCL Effect Rate Of Hydrogen Produced Aim:- To determine how temperature affects the rate at which the reaction between Magnesium ribbon (Mg) and Hydrochloric acid (HCl) takes place. Introduction:- The rate of reaction can be affected by a number of factors: temperature, concentration, adding a catalyst and surface area. The one that I am going to be investigating and explaining about is temperature. Changes in temperature change the kinetic energy of the particles and hence the numbers of successful collisions with enough energy to break existing bonds and make products. For a reaction to take place, molecules must collide with each other. When they do so, they must possess enough energy to break the intermolecular bonds and hence, cause a reaction. The two theories that affect temperature and the rate of reaction are the kinetic theory and the collision theory. The kinetic theory clearly states that the positioning and movement of particles in a substance increases if the temperature increases. Therefore, increasing the temperature increases the energy between the particles and makes them move around a lot more and collide more often. Hypothesis: - The rate of reaction has a positive relationship with the temperature of the Hydrochloric Acid. Apparatus:- ) Test tube 2) Rubber tube (a.k.a. delivery tube) 3) Measuring cylinder X2 [1-10ml, 1-100

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Chemistry Investigation on neutralisation reaction.

Chemistry Investigation on neutralisation reaction Plan Neutralisation is the reaction that occurs when an acid has its acidity, that is its hydrogen ions removed by, another chemical containing OH- hydroxide ions. Chemicals that can cancel out an acid in this way are: bases (metal oxides or hydroxides), alkalis (bases that dissolve), metals (e.g. magnesium) or metal carbonates (e.g. marble chips) All of these have a similar way of removing the hydrogen from the acids (they swap it or their metal atoms) but the reactions are quite different. They will all get quite hot if the acid is strong enough, but only the last two will make bubbles. Metals form hydrogen gas, carbonates make carbon dioxide. All of them will leave a neutral chemical after the reaction has finished, if all the acid has been used up. Titration is a technique used to calculate the concentrations or amounts of substances. In an acid base titration you may have an acid that you don't know the concentration of, and a base whose concentration you do know. The technique is to measure out accurately a volume of the alkali of unknown concentration into a flask, and fill up a burette with the acid. Add some indicator solution to the acid in the flask, so that when all the acid has reacted with the base, there will be a colour change. The burette is graduated. You then open the tap on the burette and let the acid

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Chemistry revision notes. Atomic Structure and Bonding, Electrolysis, Acids and Alkalis.

Atomic Structure and Bonding (F) Atoms, Molecules and Ions. AN ATOM is the smallest particle of an element. They cannot be split into smaller particles in chemical reactions. Iron is made of iron atoms (Fe). Sulphur is made of sulphur atoms (S) A MOLECULE is a small group of atoms joined together. The atoms may be the same (e.g. O2) or different (e.g. H2O). The chemical formula shows the number and type of atoms present. Non-metal compounds are made of molecules: Carbon dioxide contains CO2 molecules Methane (natural gas) contains CH4 molecules AN ION is an atom or group of atoms with an electrical charge (+ or -). Metal compounds such as sodium chloride or copper sulphate contain ions. Sodium chloride is made of Na+ and Cl- ions Magnesium Oxide is made of Mg2+ and O2- ions Note that metals form positive ions while non-metals form negative ions. A solid is represented by (s). e.g. H2O(s) is ice. A liquid is represented by (l) e.g. Fe(l) is molten iron. A gas is represented by (g) e.g. H2O(g) is steam. A solution in water is represented by (aq). Salt dissolved in water is NaCl(aq). You should remember that the common gases are diatomic (have 2 atoms in each molecule). These are Oxygen O2; Hydrogen H2; Nitrogen N2; and Chlorine Cl2. Elementary Particles Atoms are made up of smaller particles called protons, neutrons and electrons. The protons and neutrons

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Atmospheric pollutants in the lower atmosphere essay.

Atmospheric pollutants in the lower atmosphere The atmosphere becomes polluted by both natural processes and the activities of humans. Volcanoes can release toxic gases including sulfur dioxide. Lightning produces toxic nitrogen oxides and ozone. Let us examine some gases that pollute the lower atmosphere. Lower atmospheric pollutants often include particulates such as soot from forest fires and the exhaust from industry. Metal dusts and concrete dusts also are atmospheric pollutants, as are vapours from solvents used in industry and domestically. Carbon dioxide The concentration of carbon dioxide has shown a gradual increase during the twentieth century. The burning of fossil fuels such as coal and oil products has caused this gradual increase in carbon dioxide levels. This increase in carbon dioxide is one of the factors that scientists believe has added to global warming. This is sometimes referred to as the 'enhanced greenhouse effect'. Carbon dioxide absorbs infrared (IR) radiation that is re-radiated by the Earth's surface. This process is vital in ensuring that the Earth does not lose too much heat and become a cold, lifeless planet. Too much carbon dioxide, however, leads to higher heat retention with consequent changes to the abiotic and biotic environment. Carbon monoxide Carbon monoxide is a lower-atmospheric pollutant. Road traffic emissions account for up

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Methods of Removal of Hardness in Water

Methods of Removal of Hardness in Water Removal of Temporary Hardness By boiling the hard water Temporary hardness in water can be easily removed by boiling. On boiling, calcium/magnesium bicarbonate decomposes to give calcium/magnesium carbonate, which is insoluble in water. Therefore, it precipitates out. By the addition of slaked lime (Clark's process) In Clark's process, slaked lime, Ca(OH)2 is added to temporary hard water. Insoluble calcium carbonate precipitate out and no longer produce hardness. The methods used to remove permanent hardness given in the next section can also be employed to remove the temporary hardness. However, the above methods cannot be used to remove the permanent hardness. Methods to Remove Permanent Hardness By the addition of washing soda (sodium carbonate) Calcium and magnesium ions present in hard water react with sodium carbonate to produce insoluble carbonates. The water now contains soluble and harmless sodium salts. Calgon process Calgon is a trade name of a complex salt, sodium hexametaphosphate (NaPO3)6. It is used for softening hard water. Calgon ionizes to give a complex anion: The addition of Calgon to hard water causes the calcium and magnesium ions of hard water to displace sodium ions from the anion of Calgon. This results in the removal of calcium and magnesium ions from hard water in the form of a complex with

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Chemistry coursework - Fuels

Planning Aim In this investigation I will have to find out which of the alcohol fuels: methanol, ethanol, propanol and butanol, is the best. The 'best' one will be the one which creates the most energy whilst burning. Introduction and prediction A fuel is a substance burned for heat or power. The best type of fuel is one that: can be transported safely without the worry of it catching on fire, gives out a lot of heat for a certain mass, does not cost very much, lights quickly, burns slowly, is safe to use and does not give off any form of polluting gases. When burning alcohols, as I am going to do in this investigation, the reaction is exothermic as heat is given out. Breaking the bonds of the original alcohol by burning requires energy-it is endothermic, making the bonds of the new products of burning the alcohol ie carbon dioxide and water gives out energy-it is exothermic. I predict that Butanol will require the most energy as it has the most bonds holding the carbon, oxygen and hydrogen atoms together. Propanol will require the second largest amount of energy, Ethanol the third and Methanol the least amount of energy to break these bonds. Methanol CH3OH Ethanol C2H5OH Propanol C3H7OH Butanol C4H9OH Pentanol C5H10OH Therefore I predict that Methanol will be the 'best' fuel, followed by Ethanol, then Propanol and the worst fuel will be Butanol. Apparatus

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Rates of Reaction

Introduction In this investigation I am investigating the reaction between hydrochloric acid and calcium carbonate (known as limestone). The rate of reaction is basically the speed a reaction takes place- meaning how long it occurs for. Chemical reactions only occur when reacting particles collide with each other with sufficient energy to react. The minimum amount of energy that causes them to react is called the activation energy - simply because it activates the reaction. There are many variables that need to be taken under consideration when measuring the rate of reaction. These can include catalysts, surface area, temperature or concentration of the liquid. In this case the dependant variable is the concentration of the liquid. These variables can either decrease or increase the rate of reaction. Theoretical Background When a reaction takes place it has to overcome a minimum energy barrier known as the Activation Energy. If the particles collide with less energy than the activation energy then nothing worth noting happens. "You won't get a reaction unless the particles collide with a certain minimum energy called the activation energy of the reaction." (Taken from www.chemguide.co.uk). Only those collisions, which have energies equal to or greater than the activation energy result in a reaction taking place. The reason why collisions have to overcome the

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An Investigation Into What Affects How Much Copper Is Deposited On A Pure Copper Cathode.

An Investigation Into What Affects How Much Copper Is Deposited On A Pure Copper Cathode. Plan Aim The aim of this investigation is to find out what effects the amount of copper deposited on a pure copper cathode. We already know that by passing an electric current through a copper sulphate solution the atoms at the anode dissolve while at the cathode positive ions are gathering and collect up. Variables Variables are what we can change in the experiment here are some of them: * We can change the amount of current passed through the electrodes. * We can change the strength of the solution by adding and reducing the amount. * We can also vary how long the experiment is left while an electric current is passed through the electrodes. We choose to change the amount of current passed through the electrodes using a variable resistor. I choose this because it is simple and gives off good and clear results. Predictions A simple prediction would be to say that the mass of copper deposited at the anode would decrease, and the mass of copper deposited at the cathode would increase. It is also possible to predict when using time as a variable, that the relationship between the time the current flows and the mass of copper deposited at the cathode will be proportional. I can then predict that if I double the time of the experiment, I will be doubling

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Chem MC analysis. In which of the following cases may it obtain a complete neutralization? (1)25.0 cm3 of 0.120 M sulphuric acid and 50cm3of 0.120M sodium hydroxide solution (2)50.cm3 of 0.5 M Sodium hydroxide and 0.025 moles of aqueous ammonium chlorid

Chemistry 4A Ivan Liu Chun Pok (12) Non-practical task Mc analysis Topics: Neutralization, Reaction between alkali and ammonium compound, Strength of Acid and Alkali, Reacting Masses, Volumetric Analysis In which of the following cases may it obtain a complete neutralization? (1)25.0 cm3 of 0.120 M sulphuric acid and 50cm3of 0.120M sodium hydroxide solution (2)50.cm3 of 0.5 M Sodium hydroxide and 0.025 moles of aqueous ammonium chloride (3)20.0cm3 of 0.100M phosphoric acid and 30.0cm3 of 0.200 M potassium hydroxide solution (4)Dissolve 0.2025g of solid sodium hydroxide in water and make up to 250cm3 of solution, then 25.0cm3 of this solution is added to 50.0cm3 of 1M hydrochloric acid A.2 B.1, 3 C.3, 4 D.1, 2, 4 Option 1: H2SO4(aq) + 2NaOH(aq)--> Na2SO4(aq) +H2O(l) Mole ratio of H2SO4 : NaOH = 1:2 ?Using the formula, Molarity of a solution M or mol dm-3 = Number of moles of solute (mol) / Volume of solution (dm3) ?Number of moles of solute (mol) = Molarity of a solution M or mol dm-3X Volume of solution (dm3) Number of moles of H2SO4 given: 0.12 X (25.0 /1000) = 0.003mol Number of moles of NaOH given: 0.12 X (50.0/1000) = 0.006mol Mole ratio of H2SO4 : NaOH = 0.003 /0.006 = 1:2 Therefore, option (1) is correct. Option 2 : NaOH(aq) + NH4Cl (aq)--> NaCl(aq)+ NH3(g) + H2O(l) Mole ratio of NaOH : NH4Cl

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