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Period 3: Structure & Bonding Melting point Melting points of the elements across Period 3 table Ions of Period 3 elements with increasing positive charge (metals) and increasing of outer elect...
Properties of the Elements in Period 3 Elements in the periodic table are arranged in order of increasing atomic number and placed in vertical columns (groups) and horizontal rows (periods) The ele...
Catalysts Catalysis is the process in which the rate of a chemical reaction is increased, by adding a substance called a catalyst A catalyst increases the rate of a reaction by providing the reacta...
Activation Energy For a reaction to take place, the reactant particles need to overcome a minimum amount of energy This energy is called the activation energy (Ea) In exothermic reactions the react...
Rate of Reaction: Concentration & Pressure Concentration The more concentrated a solution is, the greater the number of particles in a given volume of solvent An increase in concentration cause...
Rate of Reaction: Collision Theory Reaction rate The rate of a reaction is the speed at which a chemical reaction takes place and has units mol dm-3 s-1 The rate of a reaction can be calculated by:...
Indicators Indicators are substances that change colour when they are added to acidic or alkaline solutions When choosing the appropriate indicator, the pH of the equivalence point is very importan...
pH Titration Curves What are pH titration curves Titration is a technique used in neutralisation reactions between acids and alkalis to determine the concentration of the unknown solution It involv...
Strong & Weak Acids & Bases Strong and weak acids can be distinguished from each other by their: pH value (using a pH meter or universal indicator) Electrical conductivity Reactivity pH An ...
