Oleum specific gravity

For solutions containing sulphuric acid only, direct titration with standard alkali, and measurement of the specific gravity, are possible as methods of estimation, provided that the process in either case is, if necessary, preceded by suitable dilution (see p. 165). Thermometric methods have also been suggested, depending on the rise in temperature when the acid is mixed with water, or when titrated with barium chloride solution.4 The water content of the concentrated acid may be determined by similar titration with oleum which has been standardised thermometrically by 80 per cent, sulphuric acid (see p. 147 ).5... 

Percent h2so4 °Be Percent Oleum (% Free SO ) Specific Gravity Uses... 

Fig. A.4. Specific Gravity of oleum versus mass% equivalent H2S04. Source Chemical Plant Control Data, 8 h Ed. 1963, Chemical Construction Corporation, New York, 43-44.

Oleum, % free SO3 % Equivalent H2SO4 Specific gravity (37.78) Freezing point (°C)... 

Figure A.4 Specific gravity of oleum versus mass% equivalent H2SO4.

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