Most naphthalene is derived from coal tar. Typical coal tar is about 10% naphthalene by weight. Naphthalene in crystallized from coal tar fraction with boiling point 210-220°C than it is washed with sulphuric acid solution to remove theophany, with diluted alkali to remove phenol and, finally, is distilled. Also naphthalene is produced from heavy petroleum fractions during petroleum refining, but today petroleum-derived naphthalene represents only a minor component of production . Coal tar is brown or black liquid of extremely high viscosity. In the coal gas era, there were many companies in Britain whose business was distil coal tar to separate the higher-value fractions, such as naphtha, creosote and pitch.
The haploid phase in plant is called:
Which among the following nutrient deficiency symptom is major veins remain green, top veins become short and slender and chlorosis on new leaf?
Which variety of mango is suitable for High-Density Planting (HDP)?
Which of the following is matched correctly?
Botanical name of lemon grass is
The vertical side of the furrow made in the soil away from which the turned soil is thrown is called
Which of the following arrangement of the crops is correct in respect of their water requirement (WR).
Which of the following is a measure to promote the export of organic products under India's Agricultural Export Policy?
Which of the following is smallest order of class Insecta?
Corrugation method of irrigation is suitable for
