A. Types of Error. A group of students is doing an analysis of copper in a 1-peso coin. They were tasked to prepare standard solutions and weigh the analyte as the end-product of their experiment. What type of error is it and explain how this type of error incurring in their experiment. Choices for Type of Error 1. Determinate error – also known as systemic error, causes the mean of a data set todiffer from the accepted value. It can cause all the results to be too high or too low. a. Instrumental error – caused by non-ideal instrument behavior, by faultycalibrations, or by use under inappropriate conditions. Calibration eliminatesmost systematic errors. b. Method error – arise from non-ideal chemical or physical behavior of analyticalsystems. It includes the slowness of some reactions, the incompleteness ofothers, instability of some species and the possible occurrence of side reactionsthat interfere with the measurement process. c. Personal error – result from carelessness, inattention, or personal limitations ofthe experimenter. Measurements sometimes require personal judgement that canlead to errors, a universal source of personal error is prejudice or bias. 2. Indeterminate error – also known as random error, causes the data to be scatteredmore or less symmetrically around a mean value. The measurement can be validatedby the precision of data. 3. Gross error – usually occur only occasionally, are often large and may result to beeither high or low. This is often the product of human errors that can lead to outliersand results appear to differ markedly from all other data in a set of replicatemeasurements. - - - - - - a.) Makisig forgot to calibrate the analytical balance before weighing. b.) Only one trial was performed in the experiment. c.) One member inadvertently recorded 29.90 mL instead of 19.90 mL volume. d.) Marikit had very good precision but poor accuracy in her data. e.) Volumetric flasks were placed inside the oven for drying before it was used. f.) Trial 1 and 2 have values close to 30.0 mL while trial 3 gave 55.0 mL. g.) The reagent used in determining copper was added incorrectly and gave a low yield.

A. Types of Error.

A group of students is doing an analysis of copper in a 1-peso coin. They were tasked to prepare standard solutions and weigh the analyte as the end-product of their experiment. What type of error is it and explain how this type of error incurring in their experiment.

Choices for Type of Error

1. Determinate error – also known as systemic error, causes the mean of a data set todiffer from the accepted value. It can cause all the results to be too high or too low.

a. Instrumental error – caused by non-ideal instrument behavior, by faultycalibrations, or by use under inappropriate conditions. Calibration eliminatesmost systematic errors.

b. Method error – arise from non-ideal chemical or physical behavior of analyticalsystems. It includes the slowness of some reactions, the incompleteness ofothers, instability of some species and the possible occurrence of side reactionsthat interfere with the measurement process.

c. Personal error – result from carelessness, inattention, or personal limitations ofthe experimenter. Measurements sometimes require personal judgement that canlead to errors, a universal source of personal error is prejudice or bias.

2. Indeterminate error – also known as random error, causes the data to be scatteredmore or less symmetrically around a mean value. The measurement can be validatedby the precision of data.

3. Gross error – usually occur only occasionally, are often large and may result to beeither high or low. This is often the product of human errors that can lead to outliersand results appear to differ markedly from all other data in a set of replicatemeasurements.

- - - - - -

a.) Makisig forgot to calibrate the analytical balance before weighing.

b.) Only one trial was performed in the experiment.

c.) One member inadvertently recorded 29.90 mL instead of 19.90 mL volume.

d.) Marikit had very good precision but poor accuracy in her data.

e.) Volumetric flasks were placed inside the oven for drying before it was used.

f.) Trial 1 and 2 have values close to 30.0 mL while trial 3 gave 55.0 mL.

g.) The reagent used in determining copper was added incorrectly and gave a low yield.