use the following information to answer the next question. during an experiment a student combines solutions…

use the following information to answer the next question. during an experiment a student combines solutions or lead(ii) nitrate and potassium iodide and collects the precipitate by filtration. pb(no3)2(aq) + 2ki(aq) → pbi2(s) + 2kno3(aq) before conducting the experiment the student uses stoichiometry to predict the expected mass of precipitate. predicted precipitate according to the students stoichiometric predictions, the mass of the precipitate is expected to be 2.30 g. experimental evidence mass of filter paper: 1.10 g mass of filter paper and precipitate: 3.20 g. 9. a possible explanation for the difference between the experimental and predicted mass of precipitate formed by the reaction is filter paper was not allowed to dry completely when the final mass was obtained. the precipitate was not adequately flushed with distilled water permitting unreacted solution to dry forming crystals on the filter paper.

use the following information to answer the next question. during an experiment a student combines solutions or lead(ii) nitrate and potassium iodide and collects the precipitate by filtration. pb(no3)2(aq) + 2ki(aq) → pbi2(s) + 2kno3(aq) before conducting the experiment the student uses stoichiometry to predict the expected mass of precipitate. predicted precipitate according to the students stoichiometric predictions, the mass of the precipitate is expected to be 2.30 g. experimental evidence mass of filter paper: 1.10 g mass of filter paper and precipitate: 3.20 g. 9. a possible explanation for the difference between the experimental and predicted mass of precipitate formed by the reaction is filter paper was not allowed to dry completely when the final mass was obtained. the precipitate was not adequately flushed with distilled water permitting unreacted solution to dry forming crystals on the filter paper.

Answer

Brief Explanations:

  1. If the filter - paper was not allowed to dry completely when the final mass was obtained, the extra water mass would increase the measured mass of the filter - paper and precipitate, making the experimental mass higher than the predicted mass.
  2. If the precipitate was not adequately flushed with distilled water, impurities or unreacted substances remaining on the precipitate could cause the experimental mass to be higher than the predicted mass due to the additional mass of these substances.

Answer:

Filter paper was not allowed to dry completely when the final mass was obtained; The precipitate was not adequately flushed with distilled water permitting unreacted solution to dry forming crystals on the filter paper.