1 / 25

Introduction to Matter and Measurement in Chemistry

This chapter discusses the fundamental concepts of matter and energy and their interactions in chemistry. Topics include atoms and molecules, classification of matter, physical and chemical changes, units of measurements, reliability of measurements, and unit conversions.

thaddeuss
Download Presentation

Introduction to Matter and Measurement in Chemistry

An Image/Link below is provided (as is) to download presentation Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author. Content is provided to you AS IS for your information and personal use only. Download presentation by click this link. While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server. During download, if you can't get a presentation, the file might be deleted by the publisher.

E N D

Presentation Transcript

  1. Chapter 1Matter and Measurement Chm 108 Suroviec Fall 2014

  2. Chemistry • Chemistry is concerned with matter and energy and how the two interact with each other • Chemistry is a foundation for other disciplines • Engineering – polymers, energy, pharmaceuticals • Health sciences • Pharmacy and pharmacology • Scientific writing

  3. I. Atoms and Molecules • Air is made of several components • Atoms are particles that constitute the fundamental building block of matter • Molecules are 2 or more molecules joined together

  4. I. Atoms and Molecules • Properties of various substances depend on the molecules and atoms that make them up • H2O vs H2O2

  5. II. Classification of Matter • Matter has mass • Not the same as weight • Matter occupies space • Phases of matter • Solids • Fixed volume and shape • Liquids • Fixed volume, indefinite shape • Gases • Indefinite shape and volume

  6. B. Elements/Compounds/Mixtures • Besides classifying by state also classify by composition • Starting with all matter ask does the composition vary if you took 2 samples • Pure substance • Mixtures

  7. Classification of Matter

  8. III. Physical and Chemical Changes • We are constantly seeing changes in matter: • Evaporate, rust, rotting, freezing, etc • But what happens to the molecules during these changes?

  9. II. Physical and Chemical Changes • physical change: does not alter the composition or identity of a substance. • chemical change: alters the composition or identity of the substance(s) involved.

  10. 01_07.JPG

  11. IV. Units of Measurements • In 1999 the US and European scientists working together on the Mars Climate Orbiter realized after they had all ready sent the satellite off that half of the measurements were in metric and half in English. The satellite was lost.

  12. Table 1.2 - Powers of Ten

  13. Table 1.3 – Units and Unit Relations

  14. IV. Units of Measurements A. Meter and Length B. Kilogram and Mass

  15. IV. Units of Measurement C. Time and seconds D. Temperature and Kelvin

  16. E. Volume and Density • Volume is measurement of space and length3 • Density • Ratio of mass to volume

  17. V. Reliability of Measurement • If we were to measure water using a beaker an then again with a graduated cylinder: • Scientific measurements are reported so that every digit is certain except the last • This digit is an estimate

  18. V. Reliability of Measurements • Significant Figures • Every measurement carries uncertainty • All measurements must include estimates of uncertainty with them • There is an uncertainty of at least one unit in the last digit • Significant figures are meaningful digits in measurements • In 8.00 mL, there are three significant figures • In 8.0 mL, there are two significant figures • In 8 mL, there is one significant figure

  19. The number of atoms in 12 g of carbon: 602,200,000,000,000,000,000,000 The mass of a single carbon atom in grams: 0.0000000000000000000000199 A. Scientific Notation 6.022 x 1023 1.99 x 10-23 N is a number between 1 and 10 N x 10n n is a positive or negative integer

  20. A. Scientific Notation Convert the following to scientific notation: 0.000 000 000 372 m (diameter of Na atom) 150,000,000m (distance from Earth to moon)

  21. B. Precision and Accuracy Accuracy – how close a measurement is to the true value Precision – how close a set of measurements are to each other accurate & precise precise but not accurate not accurate & not precise

  22. VI. Unit Conversion • In many cases throughout your study of chemistry, the units (dimensions) will guide you to the solution of a problem • Always be sure your answer is reported with both a number and a set of units!

  23. VI. Unit Conversions • Conversion factors are used to convert one set of units to another • Only the units change • Conversion factors are numerically equal to 1 • 1L = 1000 cm3

  24. VI. Unit Conversion Convert 1.00 mg into picograms Conversion Unit 1 x 1012pg = 1 g How much does a person weigh in pounds if they weigh 11.29 stone, given that 1 stone = 14 pounds. Use significant figures. How large is Australia in sq meters if 1 mile = 1609.34 meters and the land mass = 2,941,526 sq. miles?

  25. A. Problems with Equations • With these problems you are going to find one of the variables given the rest. • Find the radius in cm of a water droplet with a volume of 0.06cm2 using V = (4/3)pr2

More Related