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  Quantitative analysis deals with the determination of the amount of each component in a sample of matter. It is divided into two which include: a.    Gravimetric analysis b.    Volumetric analysis Gravimetric analysis : is interested in the measurement of mass of the substances. Volumetric analysis : is interested in the measurement of the volume of solutions.   Titration is the method used in volumetric analysis. This is done by careful addition of standard solution from a graduated container until the reaction is complete. A complete reaction is indicated by a colour change in the resulting solution. Some apparatus used for volumetric analysis These are burette, pipette, conical flask, beaker, funnel, wash bottle and volumetric flask. Standard solution is a solution of a known concentration. Basic Principles of Volumetric Analysis   Test substance or analyte, is normally a base in acid-base titration, is pipetted into the co...

Aluminium chloride is white crystal solid. It is very soluble in water and it hydrolyses in water to form acidic solution. The ease with which the anhydrous salt hydrolyses explains why hydrogen chloride fumes are evolved from it in damp air. Aluminium chloride is a covalent compound which reacts with water. The two ions in the compound are aluminium ion and Chloride ion. How to identify the Aluminium ion (cation) 1.     Test with sodium hydroxide : add a few drops sodium hydroxide solution to the solution the unknown salt. The formation of a white gelatinous precipitate which dissolves in excess sodium hydroxide solution shows that aluminium ion is present. Note: lead ions and zinc ions give similar reactions so this may not be the final test. 2.     Test with aqueous ammonia : add a few drops of aqueous ammonia to the unknown salt solution; the formation of a white gelatinous precipitate which is insoluble in excess aqueous ammonia confirms the p...

  This is a type analysis which involves the identification of the ions ( cation and anion) in a given inorganic substance. Thus, Qualitative analysis deals with the identification of the compound. To effectively identify the ions, it is necessary to be able to observe the presence of any chemical reaction which is normally recognized by ·         Colour change ·         Evolution of gas ·         Precipitation      Colour Change : colour change is associated with transition metal ions. The major cause of the colour in transition metal ions is electronic transition within the d-block level. The colour of light which show, is the colour of light which is reflected by the ion. This change of transition metal ions is common when they form a bond with water or ammonia. It is important to note that zinc does not form coloured ion, this is because zinc ...