• Home
  • Chapters Part 1
    • Chapter 1
    • Chapter 2>
      • 2.1 Scientific Notation
      • 2.2 Units
      • 2.3 Measurements of Length, Volume, and Mass
      • 2.4 Uncertainty in Measurement
      • 2.5 Significant Figures
      • 2.6 Problem Solving and Dimensional Analysis
    • Chapter 3>
      • 3.1 Matter
      • 3.2 Physical and Chemical Properties and Changes
      • 3.3 Elements and Compounds
      • 3.4 Mistures and Pure Substances
      • 3.5 Separation of Mixtures
    • Chapter 4>
      • 4.1 The Elements
      • 4.2 The Symbols
      • 4.3 Dalton's Atomic Theory
      • 4.4 Formulas of Compounds
      • 4.5 The Structure of The Atom
      • 4.6 Introduction to the Modern Concept of Atomic Structure
      • 4.7 Isotopes
    • Chapter 11>
      • 11.1 Rutherford's Atom
      • 11.2 Electromagnetic Radiation
      • 11.3 Emission of Energy by Atom
      • 11.4 The Energy Levels of Hydrogen
      • 11.5 The Bohr Model of the Atom
      • 11.6 The Wave Mechanical Model of the Atom
      • 11.7 The Hydrogen Orbitals
      • 11.8 The Wave Mechanical Model: Further Development
      • 11.9 Electron Arrangements in the First Eighteen Atoms on the Periodic Table
      • 11.10 Electron Configuration and the Periodic Table
      • 11.11 Atomic Properties and the Periodic Table
    • Chapter 12>
      • 12.1 Types of Chemical Bonds
      • 12.2 Electronegativity
      • 12.3 Bond Polarity and Dipole Moments
      • 12.4 Stable Electron Configurations and Charges on Ions
      • 12.5 Ionic Bonding and Structures of Ionic Compounds
      • 12.6 Lewis Structures
      • 12.7 Lewis Structures of Molecules with Multiple Bonds
      • 12.8 Molecular Structure
      • 12.9 Molecular Structure: The VSEPR Model
      • 12.10 Molecular Structure: Molecules with Double Bonds
    • Chapter 5>
      • 5.1 Naming Compounds
      • 5.2 Naming Binary Compounds That Contain a Metal and a Nonmetal (Types I and II)
      • 5.3 Naming Binary Compounds That Contain Only Nonmetals (Type III)
      • 5.5 Naming Compounds That Contain Polyatomic Ions
      • 5.6 Naming Acids
      • 5.7 Writing Formulas from Names
    • Chapter 6>
      • 6.1 Evidence for a Chemical Reaction
      • 6.2 Chemical Equations
      • 6.3 Balancing Chemical Equations
    • Chapter 7>
      • 7.1 Predicting Whether a Reaction Will Occur
      • 7.2 Reactions in Which a Solid Forms
      • 7.3 Describing Reactions in Aqueous Solutions
      • 7.4 Reactions That Form Water: Acids and Bases
      • 7.5 Reactions of Metals with Nonmetals (Oxidation-Reduction)
  • Chapters Part 2
    • Chapter 8>
      • 8.1 Counting by Weighing
      • 8.2 Atomic Masses: Counting Atoms by Weighing
      • 8.3 The Mole
      • 8.4 Learning to Solve Problem
      • 8.5 Molar Mass
      • 8.6 Percent Composition of Compound
      • 8.7 Formulas of Compound
      • 8.8 Calculation of Empirical Formulas
      • 8.9 Calculation of Molecular Formulas
    • Chapter 9>
      • 9.1 Information Given by Chemical Equations
      • 9.2 Mole-Mole Relationships
      • 9.3 Mass Calculations
      • 9.4 The Concept of Limiting Reactants
      • 9.5 Calculations Involving a Limiting Reactant
      • 9.6 Percent Yield
    • Chapter 13>
      • 13.1 Pressure
      • 13.2 Pressure and Volume: Boyle's Law
      • 13.3 Volume and Temperature: Charles's Law
      • 13.4 Volume and Moles: Avogadro's Law
      • 13.5 The Ideal Gas Law
      • 13.6 Dalton's Law of Partial Pressures
      • 13.8 The Kinetic Molecular Theory of Gases
      • 13.10 Gas Stoichiometry
    • Chapter 15>
      • 15.1 Solubility
      • 15.2 Solution Composition: An Introduction
      • 15.3 Solution Composition: Mass Percent
      • 15.4 Solution Composition: Molarity
      • 15.5 Dilution
      • 15.6 Stoichiometry of Solution Reactions
      • 15.7 Neutralization Reactions
      • 15.8 Solution Composition: Normality
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OBJECTIVE: To learn two methods of separating mixtures.
We have seen that the matter found in nature is typically a mixture of pure substances. For example, seawater is water containing dissolved minerals. We can separate the water from the minerals by boiling, which changes the water to steam (gaseous water) and leaves the minerals behind as solids. If we collect and cool the steam, it condenses to pure water. This separation process, called distillation, is shown in Figure 3.6. 

Distillation

Distillation is the method that uses the idea heating solutions to separate the different liquids and some solids
  • Boiling point
         - The temperature at which a liquid will boiling and evaporate.
         - Different liquids will have different boiling point
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When we carry out the distillation of salt water, water is changed from the liquid state to the gaseous state and then back to the liquid state. These changes of state are examples of physical changes. We are separating a mixture of substances, but we are not changing the composition of the individual substances. We can represent this as shown in Figure 3.7. 
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Separation undissolved solid from liquids

Filtration- separates liquid from a solid.
  • A liquid passes through the filter paper, but the particles are trapped.

Suppose we scooped up some sand with our sample of seawater. This sample is a heterogeneous mixture, because it contains an undissolved solid as well as the saltwater solution. We can separate out the sand by simple filtration. We pour the mixture onto a mesh, such as a filter paper, which allows the liquid to pass through and leaves the solid behind (see Figure 3.8). The salt can then be separated from the water by distillation. The total separation process is represented in Figure 3.9. All the changes involved are physical changes.
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We can summarize the description of matter given in this chapter with the diagram shown in Figure 3.10. Note that a given sample of matter can be a pure substance (either an element or a compound) or, more commonly, a mixture (homogeneous or heterogeneous). We have seen that all matter exists as elements or can be broken down into elements, the most fundamental substances we have encountered up to this point. We will have more to say about the nature of elements in the next chapter. 
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