laboratory indices

Indicators - Indicators are the chemicals that when added to solutions show whether the solution is acidic or basic, by a sudden change of their colour. The common indicators used and the colour changes observed are mentioned belo..

1) Clinical symptoms provide the initial indication of the kind of STD. 2) Laboratory investigations including culture microscopic observation gives some confirmation. 3) Detection of specific antigens / antibodies by ELISA or other tests. 4) In culture the organism can be isola..

Introduction - Acids, bases and salts are three main categories of chemical compounds. These have certain definite properties which distinguish one class from the other. The sour taste of many fruits and vegetables, lemon for instance, is due to various types of acids present in them. The digestive..

="col">Reactivity and Reactions Potassium K Very reactive, very rapid with cold water forming the alkah potassium hydroxide and hydrogen gas (which is ignited). 2K + 2H 2 O (l) -------> 2KOH (aq) + H 2 (g) Sodium Na Fast reaction with cold water forming the alkali sodium hydroxide and hydrogen g..

The reaction of sodium with water-the sodium melts to a silvery ball and fizzes as it spins over the water. The rapid exothermic reaction produces a colourless gas that gives a squeaky pop! with a lit splint-hydrogen. Universal indicator will turn from green to purple/violet-the strong alk..