CHAPTER 1 Matter & Measurement General, Organic, & Biological Chemistry Janice Gorzynski Smith

1. CHAPTER 1 Matter & Measurement General, Organic, & Biological Chemistry Janice GorzynskiSmith

2. CHAPTER 1: Matter & Measurement • Learning Objectives: • Definition of matter • Solids, liquids, and gases • Physical vs chemical properties and changes • Pure substances: Elements & Compounds • Mixtures: Heterogeneous vs Homogeneous • Units of the metric system & common prefixes • Measured vs exact numbers • Significant figures: identify & use in calculations • Scientific Notation • Conversion factors for calculations to cancel units • The three temperature scales • Density and Specific Gravity Smith. General Organic & Biolocial Chemistry 2nd Ed.

3. Matter Definition Matteris anything that has mass and takes up volume. • Naturally occurring: • cotton • sand • digoxin, a cardiac drug • Synthetic (human-made): • nylon • Styrofoam • ibuprofen Smith. General Organic & Biolocial Chemistry 2nd Ed.

4. Matter Solids, Liquids, Gases The Solid State: The Gas State: The Liquid State: • A solid has a definite volume. • A gas has no definite shape; it assumes the shape of its container. • A liquid has a definite volume. • It maintains its shape regardless of its container. • It takes the shape of its container. • It has no definite volume; it assumes the volume of its container. • Solid particles lie close together in a regular pattern. • Liquid particles are close together but can move past one another. • Gas particles are very far apart and move around randomly. Smith. General Organic & Biolocial Chemistry 2nd Ed.

5. Matter Physical Properties Physical properties can be observed or measured without changing the composition of the material. • color • odor • state of matter • boiling point • melting point • solubility Smith. General Organic & Biolocial Chemistry 2nd Ed.

6. Matter Chemical Properties Chemical properties determine how a substance can be converted into another substance. Chemical change is the chemical reaction that converts one substance into another (Chapters 5 and 6). Smith. General Organic & Biolocial Chemistry 2nd Ed.

7. Matter Pure Substances: Elements Pure Substances Anelementis a pure substance that cannot bebroken down by a chemical change. • A pure substance is composed of only a single component (atom or molecule). • It has a constant composition, regardless ofsample size or origin of sample. • It cannot be broken down to other pure substances by a physical change. aluminum metal (Al) Smith. General Organic & Biolocial Chemistry 2nd Ed.

8. Matter Pure Substances: Compounds Acompoundis a pure substance formed by chemically joining two or more elements. table salt (NaCl) Smith. General Organic & Biolocial Chemistry 2nd Ed.

9. Matter Mixtures All matter can be classified as either a pure substanceor amixture. Mixtures • Mixtures are composed of more than onecomponent. • They can have varying composition (anycombination of solid, liquid, and gas). • Mixtures can be separated into their componentsby a physical process. Smith. General Organic & Biolocial Chemistry 2nd Ed.

10. Matter Mixtures: Heterogeneous & Homogeneous Homogeneous Mixture Example: simple syrup Heterogeneous Mixture Example: vinaigrette Smith. General Organic & Biolocial Chemistry 2nd Ed.

11. Matter Definition http://ridenourmhs.wikispaces.com/ESUnit2

12. Measurements Metric System Each type of measurement has a base unit in themetric system. Smith. General Organic & Biolocial Chemistry 2nd Ed.

13. Measurements Common Prefixes The prefix of the unit name indicates if the unit is larger or smaller than the base unit. Smith. General Organic & Biolocial Chemistry 2nd Ed.

14. Measurements Common Prefixes The base unit of length is the meter (m). 1 kilometer (km) = 1,000 meters (m) 1 km = 1,000 m 1 millimeter (mm) = 0.001 meters (m) 1 mm = 0.001 m 1 centimeter (cm) = 0.01 meters (m) 1 cm = 0.01 m Smith. General Organic & Biolocial Chemistry 2nd Ed.

15. Measurements Common Prefixes Mass is a measure of the amount of matter in an object. Weight is the force that matter feels due to gravity. The base unit of mass is the gram (g). 1 kilogram (kg) = 1,000 grams (g) 1 kg = 1,000 g 1 milligram (mg) = 0.001 grams (g) 1 mg = 0.001 g Smith. General Organic & Biolocial Chemistry 2nd Ed.

16. Measurements Common Prefixes The base unit of volume is the liter (L). 1 kiloliter (kL) = 1,000 liters (L) 1 kL = 1,000 L 1 milliliter (mL) = 0.001 liters (L) 1 mL = 0.001 L Volume = Length x Width x Height = cm x cm x cm = cm3 1 mL = 1 cm3 = 1 cc Smith. General Organic & Biolocial Chemistry 2nd Ed.

17. Measurements Units Smith. General Organic & Biolocial Chemistry 2nd Ed.

18. Measurements Exact Numbers An exact number results from counting objects or is part of a definition. • 10 fingers • 10 toes • 1 meter = 100 centimeters An inexact number results from a measurement or observation and contains some uncertainty. • 15.3 cm • 1000.8 g • 0.0034 mL Smith. General Organic & Biolocial Chemistry 2nd Ed.

19. Measurements Significant Figures Significant figures are all the digits in a measured number including one estimated digit. All nonzero digits are always significant. 65.2 g 65.2 g 255.345 g 255.345 g 3 sig. figures 6 sig. figures Smith. General Organic & Biolocial Chemistry 2nd Ed.

20. Measurements Significant Figures Rule 1: A zero counts as a significant figure when it occurs: • between two nonzero digits 29.05 g 29.05 g 1.0087 mL 1.0087 mL 4 sig. figures 5 sig. figures • at the end of a number with a decimal place 3.7500 cm 3.7500 cm 620. lb 620. lb 5 sig. figures 3 sig. figures Smith. General Organic & Biolocial Chemistry 2nd Ed.

21. Measurements Significant Figures Rule 2: A zero does not count as a significant figure when it occurs: • at the beginning of a number 0.00245 mg 0.00245 mg 0.008 mL 0.008 mL 3 sig. figures 1 sig. figure • at the end of a number that does not have a decimal 2570 m 2570 m 1245500 m 1245500 m 3 sig. figures 5 sig. figures Smith. General Organic & Biolocial Chemistry 2nd Ed.

22. Measurements Significant Figures: Multiplication & Division Multiplication/Division Rules: The answer has the same number of significant figures as the original number with the fewest significant figures. 4 sig. figures 351.2 miles 351.2 miles 63.854545 miles = hour 5.5 hour 5.5 hour Answer must have 2 sig. figures. 2 sig. figures Smith. General Organic & Biolocial Chemistry 2nd Ed.

23. Measurements Significant Figures: Multiplication & Division to be retained to be dropped 63.854545 miles 63.854545 64 miles = hour hour first digit to be dropped 2 sig. figures Answer If the first digit to be dropped is: Then: • between 0 and 4 • drop it and all remaining digits • between 5 and 9 • round up the last digit • to be retained by adding 1 Smith. General Organic & Biolocial Chemistry 2nd Ed.

24. Measurements Significant Figures: Addition & Subtraction Addition/Subtraction Rules: The answer has the same number of decimal places as the original number with the fewest decimal places. 10.11 kg 10.11 kg 2 decimal places 3.6 kg 3.6 kg 1 decimal place 6.51 kg answer must have 1 decimal place final answer 1 decimal place 6.5 kg = Smith. General Organic & Biolocial Chemistry 2nd Ed.

25. Measurements Scientific Notation In scientific notation, a number is written as: y x 10x Exponent: Any positive or negative whole number. Coefficient: A number between 1 and 10. Smith. General Organic & Biolocial Chemistry 2nd Ed.

26. Measurements Scientific Notation • When the exponent x is positive, move thedecimal point x places to the right. 2.800 x 102 = 280.0 • When the exponent x is negative, move thedecimal point x places to the left. 2.80 x 10–2 = 0.0280 Smith. General Organic & Biolocial Chemistry 2nd Ed.

27. Measurements Conversion Factors • Conversion factor: A term that converts a quantity in • one unit to a quantity in another unit. desired quantity original quantity x conversion factor = • Conversion factors are usually written as equalities. 2.21 lb = 1 kg • To use them, they must be written as fractions. 2.21 lb 1 kg 1 kg 2.21 lb or Smith. General Organic & Biolocial Chemistry 2nd Ed.

28. Measurements Conversion Factors Factor-label method: Using conversion factors toconvert a quantity in one unit to a quantity in another unit. • units are treated like numbers • make sure all unwanted units cancel To convert 130 lb into kilograms: 130 lb x ? kg conversion factor = original quantity desired quantity Smith. General Organic & Biolocial Chemistry 2nd Ed.

29. Measurements Conversion Factors 2.21 lb 1 kg Answer 2 sig. figures 130 lb x or 1 kg 2.21 lb = 59 kg • The bottom conversion factor has • the original unit in the denominator. • The unwanted unit lb cancels. • The desired unit kg does not cancel. Smith. General Organic & Biolocial Chemistry 2nd Ed.

30. Measurements Temperature Temperatureis a measure of how hot or cold an object is. • Three temperature scales are used: Degrees Fahrenheit (oF) Degrees Celsius (oC) Kelvin (K) To convert from oF to oC: To convert from oC to oF: oC = oF− 32 1.8 oF = 1.8(oC) + 32 To convert from oC to K: To convert from K to oC: K = oC + 273 oC = K − 273 Smith. General Organic & Biolocial Chemistry 2nd Ed.

31. Measurements Temperature Smith. General Organic & Biolocial Chemistry 2nd Ed.

32. Measurements Density Density: A physical property that relates the mass of a substance to its volume. mass (g) density = volume (mL or cc) To convert volume (mL) to mass (g): To convert mass (g) to volume (mL): g mL mL x = g g x = mL mL g inverse of density density Smith. General Organic & Biolocial Chemistry 2nd Ed.

33. Measurements Specific Gravity Specific gravity: A quantity that compares the density of a substance with the density of water at the same temperature. density of a substance (g/mL) density of water (g/mL) specific gravity = • The units of the numerator (g/mL) cancel the • units of the denominator (g/mL). • The specific gravity of a substance is equal to its • density, but contains no units. Smith. General Organic & Biolocial Chemistry 2nd Ed.