CMY 117 theme one Certification Review Exam Questions And Correct Detailed Answers.

What are physical changes - correct answer changes in the physical structure of mat Matter - correct answer anything that takes up space and has mass What are the two main divisions of matter? - correct answer Pure substances (2) and mixtures (2) What are chemical properties? - correct answer Property that becomes evident during a chemical reaction ter, the same chemicals exist after the change What are extensive properties? - correct answer properties that depend on the amount of matter that is present and can't be used to identify a substance What are intensive properties? - correct answer properties that do not depend on the amount of matter present and can be used for identification What is a physical change? - correct answer A change in a substance that does not involve a change in the identity of the substance What is a chemical change? - correct answer a change that produces matter with a different composition than the original matter qualitative observation - correct answer An observation that describes using your 5 senses. It also uses NO numbers. quantitative observation - correct answer An observation that deals with a number or amount What is accuracy? - correct answer a measure of how close a measurement comes to the actual or true value of whatever is measured What is precision? - correct answer how close a series of measurements are to one another percentage error formula - correct answer experimental value-accepted value/accepted value x 100 Uncertainty in Measurement - correct answer A digit that must be estimated is called uncertain. A measurement always has some degree of uncertainty. Due to human and equipment error Counted numbers and defined numbers are certain Rules for significant figures - correct answer Non-zero digits are always significant. Any zeros between two significant digits are significant. A final zero or trailing zeros in the decimal portion ONLY are significant. dimensional analysis - correct answer Expressing a value in another unit