Determination of the Solubility of Calcium Hydroxide

Measurement of solubility of calcium hydroxide apparatus 250 cm 3 measuring flask 25 cm 3 pipette pipette pump burette 250 cm 3 conical flask small funnel rubber stopper white tile burette clamp G clamp laboratory support 25 cm 3 hydrochloric acid solution @ 0.3 mold m - 3 225 cm 3 distilled water Excess A Base Orange indicator Excess calcium hydroxide solution @ 0.015 moldm - 3 Excessive distilled water (for washing glassware) The prepared hydrochloric acid solution has a very high concentration hydrochloric acid solution compared to the calcium hydroxide concentration.

In order to neutralize 25 cm of calcium hydroxide of unknown molar concentration, 04 mol / dm of hydrochloric acid was necessary. The solubility of the calcium hydroxide can then be calculated using the formula Ca (OH) (aqueous solution) + 2 HCl CaCl (aqueous solution) + 2 H 2 O. The molar amount of hydrochloric acid required to neutralize an unknown amount of 25 cm 2 of calcium is calculated as the amount of hydrochloric acid × 0.04 1000. The molar ratio of calcium hydroxide used in this formula depends on the ratio of 2 mol of hydrochloric acid to 1 mol of calcium hydroxide. The number can be calculated by dividing the answer. Up

As we know the molar number of 25 cm, we can calculate the number of moles of calcium hydroxide per day. This is done by multiplying the previous answer by 40 (1000/25). It is now necessary to calculate the quality of calcium hydroxide formulation. Ca (OH) 40 + (2 × 16) + (2 × 1) = 74 g This is a mass of 1 mol. To calculate the mass of calcium hydroxide at 1 dm it is necessary to obtain the answer (molar quantity of 1 dm) from the previous one and multiply the quality of the formula by 74 g. Therefore, solubility of calcium hydroxide at g dm at room temperature was found.

In the pool, hard water seems to be cloudy or muddy (milky white). Both calcium hydroxide and magnesium hydroxide are soluble in water. The solubility of the alkaline earth metal hydroxide (Group 2 of the periodic table) to which calcium and magnesium belong is increased as it falls. The aqueous solutions of these metal hydroxides absorb carbon dioxide from the air and form insoluble carbonate, which causes turbidity. This is usually due to excess pH (pH> 7.6). Therefore, a general solution to this problem is to lower the pH by adding hydrochloric acid while maintaining the chlorine concentration at an appropriate level, the optimum value being in the range of 7.2 to 7.6 .