paraphrase two body paragraphes
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Part 1 Summary: A titration is a volumetric technique in which a solution of one reactant (the titrant) is added to a solution of a second reactant (the analyte) until the equivalence or the equilibrium point is reached. This equilibrium point is the point at which titrant has been added in exactly the right quantity to react stoichiometrically with the analyte. If either the titrant or analyte is colored, the equilibrium point is evident from the disappearance of color as the reactants are consumed. In the titration of an acid by a strong base, the hydroxide ions (OH-) reacts with the acidic hydrogen atom. In the equilibrium or the stoichiometric point, the moles (n) of the hydroxide added exactly equals the moles (n) of acidic hydrogen atoms initially present in the titration. n hydroxide atom = n acidic hydrogen To measure the amount of moles (n), we can measure the mass (m) and the volume (V). The molar mass (MM) and concentration (M) provide connections between these measured quantities and the amount of moles. n = m/MM and n = M V The reason for the importance of calculating the equivalent mass (EM) is that we can get it from the results of titration without knowing how many acidic hydrogen atoms an unknown substance contains. For example, if we have 0.17 grams (macid) of an unknown acid with a solution of strong base with a concentration of 0.1865 M (Mbase) that requires a volume of 15 mL (Vbase) to reach the stoichiometric point. We can get the number of moles of the acidic hydrogen atoms by dividing the mass of the acid by the equivalent mass, so the equality at the stoichiometric point is: Mbase Vbase = macid / EM acid After rearranging this expression, we can come up with another expression that can calculate the equivalent mass of the acid in terms of the measured quantities: EMacid = macid / Mbase Vbase As a result for the example, we calculate the equivalent mass by using the equation mentioned above: EM = 0.17 g /…
Part 1 Summary: A titration is a volumetric technique in which a solution of one reactant (the titrant) is added to a solution of a second reactant (the analyte) until the equivalence or the equilibrium point is reached. This equilibrium point is the point at which titrant has been added in exactly the right quantity to react stoichiometrically with the analyte. If either the titrant or analyte is colored, the equilibrium point is evident from the disappearance of color as the reactants are consumed. In the titration of an acid by a strong base, the hydroxide ions (OH-) reacts with the acidic hydrogen atom. In the equilibrium or the stoichiometric point, the moles (n) of the hydroxide added exactly equals the moles (n) of acidic hydrogen atoms initially present in the titration. n hydroxide atom = n acidic hydrogen To measure the amount of moles (n), we can measure the mass (m) and the volume (V). The molar mass (MM) and concentration (M) provide connections between these measured quantities and the amount of moles. n = m/MM and n = M V The reason for the importance of calculating the equivalent mass (EM) is that we can get it from the results of titration without knowing how many acidic hydrogen atoms an unknown substance contains. For example, if we have 0.17 grams (macid) of an unknown acid with a solution of strong base with a concentration of 0.1865 M (Mbase) that requires a volume of 15 mL (Vbase) to reach the stoichiometric point. We can get the number of moles of the acidic hydrogen atoms by dividing the mass of the acid by the equivalent mass, so the equality at the stoichiometric point is: Mbase Vbase = macid / EM acid After rearranging this expression, we can come up with another expression that can calculate the equivalent mass of the acid in terms of the measured quantities: EMacid = macid / Mbase Vbase As a result for the example, we calculate the equivalent mass by using the equation mentioned above: EM = 0.17 g /…
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