36 mgl the experimental average solubility product

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is calculated to be 2900.36 mg/L. The experimental average solubility product constant for Mg(OH) 2 is 8.23 x 10 -11 . The literature value of the constant is 5.61 x 10 -12 . The experimental average solubility product constant for Ca(OH) 2 is 3.81 x 10 -7 . The literature value of the constant is 5.02 x 10 -6 . The experimental average solubility product constant for Sr(OH) 2 is 7.93 x 10 -5 . The literature value of the constant is 6.43 x 10 -3 . It is observed that the experimental average solubility product constants are different than the literature values provided by credible sources. There could be a number of reasons behind this difference. In a realistic laboratory environment, it is very difficult to ensure that only the desired chemical compounds and species are present within the system. Generally there might be other chemicals present within the system that can potentially affect the outcome of the experiment. A possible cause for this type of error is unclean apparatus. The equipments and apparatuses used in the experiment might have not been cleaned completely or thoroughly, resulting in contamination of other chemicals. Presence of other chemical species in the process of titration could have altered the solubility of the solutions being titrated and thus changed the solubility product constant as well. Another possible source of error might be addition of too much phenolphthalein. Phenolphthalein is an acidic compound and thus adding too much of the indicator to the basic solutions would have lowered the concentration of [OH] - , making it more acidic. If the basic solutions had lowered pH, it would have taken less HCl to neutralize it. Despite the difference between experimental solubility constants and the literature values, the trend in solubility in terms of periodic groups can be observed in both. The solubility constant gets bigger going down a group, which implies that solubility of a hydroxide increases going down a group [Refer to Table 1]. This can be explained through the periodic trend of ionization energy, the amount of energy needed to remove an electron from an atom or an ion. As an atom gets bigger, the forces holding the electrons together become weaker and that makes it easier to remove an electron. In other words, ionization energy decreases as the atom gets bigger. Atomic size gets bigger going down a group so ionization energy decreases with that. The lesser energy it takes to form a cation, the more soluble it is.
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Calculations 1. Calculating the moles of acid: C = n/V where C represents the concentration, n represent the number of moles and V represents the volume of the chemical species or solution.
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