Evaluating Scientific Explanations — Unit test Answers

Henry plans to monitor the change in concentration of an acid during a chemical reaction. He wants to collect data every 0.1 seconds and then to graph his data and insert it into a text document. Which pair of tools would be best for Henry to use?

A company that manufactures cookware has conducted numerous trials to see which metal needs the least amount of energy (measured in Joules, J) to be raised to high temperatures, and records the averages in a table. Which claim will this company most likely make?

Read the passage about the fluoridation of drinking water.Since the early 1960s, fluoride has been added to many sources of drinking water to prevent cavities in teeth. This is called fluoridation. There are some who say that this is unnecessary and increases the risk of cancer.In 1993, the Subcommittee on Health Effects of Ingested Fluoride of the National Research Council, part of the National Academy of Sciences, conducted an extensive study about the link between fluoridated drinking water and increased cancer risk. The study included data from more than 50 human disease studies and six animal studies. The Subcommittee concluded that none of the data showed a link between fluoridated drinking water and cancer. A 1999 report by the CDC supported these findings. The CDC report concluded that studies so far have produced "no credible evidence” of a link between fluoridated drinking water and an increased risk for cancer.

What information in the MSDS would be most important to know at the end of an experiment?

In what way would a digital thermometer be preferable to those from a liquid-based thermometer?

Scientists often work on projects for a long time and fail to see sources of error in their research. Which process allows an outside expert to look at the scientist’s project and point to sources of error?

Which practice poses the greatest safety concern?

The MSDS for sodium hydroxide gives it a health rating of 3, a flammability rating of 0, and a reactivity rating of 1. According to the MSDS, which best describes sodium hydroxide?

The MSDS for glacial acetic acid says that it is a flammable liquid that can severely burn any human tissue it comes in contact with. It reacts with bases, various metals, and strong oxidizing agents. Its vapors can form explosive mixtures with air. Based on this information, which statement is applicable to glacial acetic acid?

Vincent graduated from college with a degree in horticulture and now owns a local plant nursery. He maintains a blog titled, "How to Live a Happy Life,” and writes that people can lead happier lives by varying the routes they usually take home from work.

A series of experiments, which are repeated over and over, seem to suggest that a scientific theory is incorrect. What does this most likely mean?

A student is creating a table that compares theories, hypotheses, and laws. TheoryHypothesisLawIs testable Is falsifiable Is used to make predictions Provides explanations In which row should the student enter “Yes” in the columns for Theory and Hypothesis only?

Which term best describes the important pieces of information that scientists gather and record during an experiment?

In an investigation that uses the scientific method, which step immediately follows asking a question?