Situation Clyde is an engineer in charge of a chemical process that runs continuously for about eight hours to make a batch of a specific chemical. Recently, Clyde has suspected that some of the quality characteristics, such as purity and particle size, have shown an increase in variation for the chemical. The characteristics’ measured values have been within specifications, but Clyde is convinced that the process has changed. He just can’t prove it. After looking at the data and coming up empty, Clyde decided to look at several process variables. Of particular interest is the process temperature, which is recorded twice during each production run for a batch. Available data Temperature data for batches of this chemical produced between July 30 and Sept. 4 are shown in the table, Temperature Data for Chemical Process. The plant runs five days a week and the chemical is produced on the day shift. Questions 1. Is the process temperature required for producing this chemical behaving in a predictable manner? 2. Is the process temperature meeting the process specifications? 3. What evidence, if any, can be found in these data to explain an increase in the variability of the quality characteristics for the finished product?
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