1 / 30

Properties of Matter

Properties of Matter. Intensive Properties: Independent of the amount of the substance that is present. Density, boiling point, color, etc. Extensive Properties: Dependent upon the amount of the substance present. Mass, volume, energy, etc. Units of Measurement. SI Units.

amanda-beasley
Download Presentation

Properties of Matter

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. Properties of Matter • Intensive Properties: • Independent of the amount of the substance that is present. • Density, boiling point, color, etc. • Extensive Properties: • Dependent upon the amount of the substance present. • Mass, volume, energy, etc.

  2. Units of Measurement

  3. SI Units • Système International d’Unités (International System of Units) • Uses a different base unit for each quantity

  4. SI Prefixes Prefixes convert the base units into units that are appropriate for the item being measured.

  5. Temperature • The Kelvin is the SI unit of temperature. • It is based on the properties of gases. • There are no negative Kelvin temperatures.

  6. Temperature • The Fahrenheit scale is not used in scientific measurements. F = 9/5(C) + 32 C = 5/9(F − 32) K = C + 273.15 1.8=9/5

  7. m V d= Derived SI UnitesVolume and Density Volume = (length)3

  8. Uncertainty in Measurement

  9. Uncertainty in Measurements Different measuring devices have different uses and different degrees of accuracy.

  10. Accuracy versus Precision • Accuracy refers to the proximity of a measurement to the true value of a quantity. • Precision refers to the proximity of several measurements to each other.

  11. Significant Figures • The term significant figures refers to digits that were measured. • When rounding calculated numbers, we pay attention to significant figures so we do not overstate the accuracy of our answers.

  12. Significant Figures • All nonzero digits are significant. • Zeroes between two significant figures are themselves significant. • Zeroes at the beginning of a number are never significant. • Zeroes at the end of a number are significant if a decimal point is written in the number.

  13. All nonzero digits are significant. • Examples: • 0.12345 • 1234567

  14. Zeros between significant figures are significant • Examples: • 10234 • 20055

  15. Zeros preceding the first nonzero digit are not significant • Examples: • 0076891 • 0.00034

  16. Zeros to the right of the decimal after a nonzero digit are significant. • Examples: • 9.000 • 0.910

  17. Zeros at the end of a nondecimal number may or may not be significant (Use scientific notation) • Examples: • 900? 1? or 2? or 3?

  18. Significant Figures in Calculations

  19. = 0.137 g/mL only three significant figures 1. Multiplication and Division answers are rounded to the number of digits that corresponds to the least number of significant figures in any of the numbers used in the calculation. 14.0 g /102.4 mL = ? g/mL

  20. Only one decimal place 2. Addition and Subtraction answers are rounded to the least significant decimal place. 184.2 g + 2.324 g = 186.524 g

  21. Exact Numbers • An exact number is a number that arises when you count items or when you define a unit. • When you say you have nine coins in a bottle, you mean exactly nine. • When you say there are twelve inches in a foot, you mean exactly twelve. • Note that exact numbers have no effect on significant figures in a calculation.

  22. What is the total mass of 9 coins, when each coin has a mass of 3.0 grams? Infinite no. of Sig. Fig. Two sig. Fig. An Example

  23. Rounding • Rounding is the procedure of dropping nonsignificant figures in a calculation result and adjusting the last digit reported. Example: rounding 1.2151 to 3 sig. Fig. gives 1.22 rounding 1.2143 to 3 sig. Fig. Gives 1.21

  24. Answer 3.6 0.37 Using Significant Figures in Calculations 5.01

  25. Final answer is -17 Using Significant Figures in Calculations

  26. Dimensional Analysis and Conversion of Units

  27. Units: Dimensional Analysis • In performing numerical calculations, it is good practice to associate units with each quantity.

  28. Note that the units have cancelled properly to give the final unit of feet. Units: Dimensional Analysis • Suppose you simply wish to convert 20 yards to feet. Conversion factor:1 yard = 3 feet

  29. Unit Conversion • Suppose you wish to convert 0.547 lb to grams. • Knowing that 1 lb = 453.6 g, so the conversion factor from pounds to grams is 453.6 g/1 lb.

  30. Operational Skills • Classification of Matter • Properties of Matter (Physical and Chemical) • Separation of Mixtures • Accuracy and Precision • Unit of Measurement and Unit systems • Prefixes Used in Metric System • Using significant figures in calculations. • Converting from one temperature scale to another. • Dimensional Analysis and Conversion of units.

More Related