By Jeffrey Medina

Section 1 Energy Energy- “is the capacity to do some kind of work, such as moving an object, forming a new compound, or generating light.” “A physical change affects only the physical properties of matter.” “A chemical change occurs whenever a new substance is made.” Evaporation- “is the change by which any substance is converted from a liquid state into and carried off in vapor.”

Section 2 Studying matter and energy Scientific method- “is a series of steps followed to solve problems, including collecting data, formulating a hypothesis, testing the hypothesis, and stating conclusions.” “Scientific discoveries can come from unexpected observations.” “Synthetic dyes were made in 1856 by William Perkin.” Hypothesis- “a reasonable and testable explanation for observations.”

Section 2 continued Theory- “is a well- tested explanation of observations.” “The law of conservation of mass states that the products of a chemical reaction have the same mass as the reactants have.” “Models can illustrate the microscopic world of chemistry, and also show what happens during a between a hyrdrogen molecule and an oxygen atom.”

Section 3 measures and calculations in chemistry Accuracy- “a description of how close a measurement is to the true value of the quantity measured.” Precision- “is the exactness of a measurement.” “The buret can measure small intervals, but should not be used for all volume requirements.” Significant figures- “a prescribed decimal place that determines the amount of rounding off to be done based on the precision of the measurement.” “Scientists always report values using significant figures.”

Section 3 continued “Significant figures are important for reporting results.” “The last digit or significant figure reported after a measurement is uncertain or estimated.” “Calculators do0 not identify significant figures.” “Exact values have unlimited signifcant figures.” “A count value is determined by counting and is an example of an exact value.” “Another value that can have an unlimited number of significant figures is a conversion factor.”

Citation Meyers, R. Thomas,et al. Holt Chemistry. Austin, TX Rienhart & Winston, Slide 2- pg Slide 3- pg Slide 4- pg Slide 5- pg Slide 6- pg 59-63