advantages and disadvantages of chemistry as scienceimages

Fire caused due to the burning of solid propellants is very difficult to contro..

1) More efficient than conventional cells because the energy of the fuel is converted directly into electric energy. Efficiency = 60-70%. 2) They are free from polluti..

High calorific value Complete combustion: No residue No smoke No pollutants Burns readily, preheating not required. This is because it has a low ignition temperature..

The advantages of distillation under reduced pressure are: The compounds that decompose on heating to their boiling points can be purified by distillation under reduced pressure. This is because at the reduced pressure, a liquid would boil at a temperature much below its normal boiling..

Reduces burden on forests and fossil fuels Produces a clean fuel - helps in controlling air pollution Provides nutrient rich (N & P) manure for plants Controls water pollution by decomposing sewage, animal dung and human excreta..

1. It is economical since there is no wastage of sulphur. 2. Sulphur of 99.5% purity is obtained. Thus it need not be further purified. 3. The process is simple and cost effective. 4. The process is continuous and does not requite rebuilding of structur..

Soaps are not suitable when hard water is used. Detergents can be used with both hard and soft water. Detergents are more soluble in water than soaps. They also have a stronger cleansing action than soaps. Detergents don't need expensive vegetable oil for their preparation as they can be prepared ..

Sodium metal obtained has high degree of purity (99.5%). The starting material, sodium chloride is very cheap. Chlorine is obtained as a useful by-product..

Expensive Steel drum may rust Requires maintenanc..

1. The classification of elements is based on the atomic number, which is a more fundamental property. 2. The reason for placing isotopes at one place is justified as the classification is on the basis of atomic numbe..