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Define ebullioscopic constant?

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Ebullioscopic constant:The ebullioscopic constant is also called the molal elevation constant.It is defined as the elevation in boiling point when one mole of non-volatile solute is added to one kilogram of solvent.It is denoted by Kb.The unit of an ebullioscopic constant is K Kg mol-1.Elevation in boiling point:Boiling point elevation refers to the increase in the boiling point of a solvent upon the addition of a solute. When a non-volatile solute is added to a solvent, the resulting solution has a higher boiling point than that of the pure solvent. Therefore, $∆{\mathrm{T}}_{\mathrm{b}}={\mathrm{T}}_{\mathrm{b}}-{{\mathrm{T}}^{°}}_{\mathrm{b}}$For example: The boiling point of a solution of sodium chloride ($\mathrm{NaCl}$) and water is greater than that of pure water.Boiling point elevation is a colligative property of matter, that is it is dependent on the solute-to-solvent ratio but not on the solute’s identity. This implies that the elevation in the boiling point of a solution depends on the amount of solute added to it. The greater the concentration of solute in the solution, the greater the boiling point elevation.Experimentally, it has been shown that the elevation of the boiling point (ΔTb​) for dilute solutions is directly proportional to the molal concentration of solute in the solution.Therefore, we can write: $∆{\mathrm{T}}_{\mathrm{b}}=\mathrm{i}×{\mathrm{K}}_{\mathrm{b}}×\mathrm{m}\phantom{\rule{0ex}{0ex}}\mathrm{where},\mathrm{i}=\mathrm{Van}\text{'}\mathrm{t}\mathrm{Hoff}\mathrm{factor}\phantom{\rule{0ex}{0ex}}{\mathrm{K}}_{\mathrm{b}}=\mathrm{ebullioscopic}\mathrm{constant}\phantom{\rule{0ex}{0ex}}\mathrm{m}=\mathrm{molality}\mathrm{of}\mathrm{the}\mathrm{solute}$

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