I'm assuming you need to know the percentage yield of the reaction
To calculate the percentage yield = (actual yield x 100%) / predicted yield
actual yield is 56,9 g
predicted yield is 36,6g ( is the amount that's expected if nothing had got lost)
(56,9 x100)/36,6=
= 155%
It would be classified as decomposition reaction
It is important in gravimetric analysis to add an excess amount of precipitating ions to a solution containing an analyte because it helps to determine the mass of the analyte.
<h3>What is Gravimetric analysis?</h3>
This is a method which is used in the determination of the quantitative determination of the ion being analyzed(analyte) based on its mass.
Adding an excess amount of precipitating ions to a solution containing an analyte will make it easier for the mass of an analyte to be determined.
It is also important for the precipitate to be a pure substance with a definite and known composition which therefore makes it the most appropriate reason.
Read more about Gravimetric analysis here brainly.com/question/6163057
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