Wednesday, October 30, 2019
Effect of Concentration and Temperature on the Rate of Reaction Essay
Effect of Concentration and Temperature on the Rate of Reaction - Essay Example An understanding of what have an effect on the speed of a reaction and how it can be changed is consequently very significant to a chemist. A higher concentration of reactants leads to more effective collisions per unit time, which leads to an increasing reaction rate (except for zero order reactions). Similarly, a higher concentration of products tends to be associated with a lower reaction rate. Use the partial pressure of reactants in a gaseous state as a measure of their concentration. Usually, an increase in temperature is accompanied by an increase in the reaction rate. Temperature is a measure of the kinetic energy of a system, so higher temperature implies higher average kinetic energy of molecules and more collisions per unit time. A general rule of thumb for most (not all) chemical reactions is that the rate at which the reaction proceeds will approximately double for each 10C increase in temperature. Once the temperature reaches a certain point, some of the chemical species may be altered (e.g., denaturing of proteins) and the chemical reaction will slow or stop. Each member of Alkanoic acids has one carboxyl group. Alkanoic acids are therefore aliphatic monocarboxylic acids. Consequently, we an represent the series with the formula RCOOH. The hydrogen atom in the carboxyl group can form a hydrogen ion in aqueous solution. Hence, members of the series are monobasic acids. Methanoic acid has a corrosive action on the skin. It occurs in the stings of ants, bees and stinging nettles (Blackburn, 1999). Properties of Methanoic acid They are weak monobasic acids. They turn litmus red, liberate hydrogen from liberate hydrogen from metals above hydrogen in the activity series and they react with bases and carbonates. Methanoic acid is the strongest acid in the series. The salts produced from the reaction is known as Methanoates (Blackburn, 1999) They react with alcohol to form esters and water. The reaction is reversible and a good yield of ester is only possible if a catalyst, such as concentrated sulphuric acid is present. Normally we use a large excess of alcohol (Blackburn, 1999). Esters are sweet smelling liquid or solids. They are used to make perfumes or artificial flavorings. Esters are not very reactive. The most important reaction of an ester is its conversion back to the acid and alcohol from which it is derived. This is known as hydrolysis. It is performed by boiling with a mineral acid or better with an alcoholic alkaline solution (Blackburn, 1999). Bromine Symbol: Br Atomic Number: 35 Period: 4 Common valence: 1, 3, 5, and 7 Atomic Weight: 79.904 Natural State: Liquid Common Isotopes: Bromine has 2 stable isotopes, bromine-79 and bromine-81, which occur in about equal proportions in nature. There are several known radio isotopes. PROPERTIES: Bromine is
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