Chemistry Notes

Q.1. What is crystallite and colloidal particle ? Crystallite particle : the particle which can passes through the semi permeable membrane are known as crystallite particle.         The size of crystallite particle is less than that of 10 cm. Eg : sugar, urea, salt solution. Colloidal particle : the particle which cannot pass through the semipermeable membrane are known as colloidal particle.      The size of colloidal particle is between 10 – 10 cm. Eg : starch, protein, albumin, gelatin. Q.2. What is suspension ? Suspension : the particle whose size is more than 10 cm and which make heterogeneous solution with solvent is known as suspension. Eg : muddy water, barium sulphate solution etc. Q.3. what is true solution ?         True solution : the solution in which the size of the particle is less than 10 cm, 10m or 1nm that solution is known as true solution. Eg : aqueous solution of sugar, salt. Q.4. what is collo...

PVC (POLYVINYL CHLORIDE)       Its monomer unit is vinyl chloride.    PREPARATION            Vinyl chloride is prepared by the treatment of acetylene and HCl in presence of HgCl2 at 100 -200°C temperature.        A mixture of liquid vinyl chloride and per sulphate catalyst such as sodium per sulphate (Na2S2O8) and H2O are taken in a reactor and shaken vigrously when tiny globules like latex is produce. It is then introduce in a autoclane at 40 - 45 °C temperature. The reaction is get completed at about 72 hours.                  The polymer particles are then recovered by coagulation by an acid solution. It is then filtered and dried and moulded according to properties desired by using plasticiser, lubricants filter etc.              PROPERTIES OF PVC Polyvinyl chloride are chemically inert and does not react with acid and ...