Integ. Science Assignments Take Notes: Page 2 – 10/11 Page 18 – 25 Define Key Terms listed on Page 26 Notes-sheet Prompt Location Due Date Textbook/ Notebook Monday Textbook/ Notebook WorksheetToday

Qualitative Observations Observations that are not mathematical or measurable. Observations made using our senses: Examples: –Color, shape, size, odor/smell, texture, etc. No measurements are used. We use our senses.

Quantitative Observations Observations that are obtained through the use of instruments and are mathematical – They have numbers. Examples: –Length, area, mass, weight, etc… Measurements are utilized.

Math: Language of Science Quantitative observations are collected as data and recorded. Numerical data allows us to search for patterns and relationships between variables. Numerical data can also be plotted on a graph for another way to look at patterns.

Data from Experiments Let’s talk about the Mice/Nicotine Experiment Testing relationship between... Nicotine and Cancer in mice Eliminate variables out of our control (i.e. diet, age, etc) by keeping mice the same What’s our experimental variable again? What is our control group doing?

Group # Amt. Nicotine (mg) Amt. of Cancerous Cells

Terminology Precision – Reproducibility, Consistency of Measurement Accuracy – Closeness to true value Reliability – Trustworthiness of measurement, depends on Measurer and the Measuring Device. Uncertainty – Questionability regarding the precision, accuracy, or reliability of a measurement or calculation.

Precision and Accuracy When making measurements in science you want them to be both precise and accurate.

Precision and Accuracy Precision indicates degree of reproducibility of a measured number. Accuracy indicates how close your measurements are to the true value.

Reliability and Uncertainty Reliability – Trustworthiness of measurement. It depends on 1) The Measurer and 2) The Measuring Device. Uncertainty – Questionability regarding the precision, accuracy, or reliability of a measurement or calculation. The last significant number in any measurement is the most uncertain digit

Accuracy and Precision

Significant Figures It is important to record the precision of your measurements so that other people can understand and interpret your results. A common convention used in science to indicate precision is known as significant figures. Significant figures are those digits in a measurement that are known with certainty plus the first digit that is uncertain.

Significant Figures Even though this ruler is marked in only centimeters and half-centimeters, if you estimate, you can use it to report measurements to a precision of a millimeter.

Rules for Sig Fig Rule 1 Zeros between other nonzero digits are significant. Examples a.50.3 m has three significant figures b s has five significant figures

Rules for Sig Fig Rule 2 Zeros in front of nonzero digits are not significant. Examples a has three significant figures b s has one significant figure

Rules for Sig Fig Rule 3 Zeros that are at the end of a number and also to the right of a decimal point are significant. Examples a g has four significant figures b kg has seven significant figure

Rules for Sig Fig Rule 4 Zeros that are at the end of a number but left of the decimal point are not significant. Examples a.100 m has ONE significant figure b.20 m has ONE significant figure

Rules for Sig. Fig. Extra Rule Zeros that are at the end of a number but left of the decimal point that are measured to be significant are indeed significant. Examples a.A scale measures kg has four significant figures and is written in scientific notation: x 10 kg so Rule 3 applies 3