Advanced chemistry notes
Download
1 / 23

Advanced Chemistry Notes - PowerPoint PPT Presentation


  • 76 Views
  • Uploaded on

Advanced Chemistry Notes. Solution Notes. Solutions. Solutions – homogeneous mixtures of two or more substances Made up of: Solvent – substance that does the dissolving Solute – substance being dissolved Examples of Solutions Kool-Aide: water – solvent, sugar – solute

loader
I am the owner, or an agent authorized to act on behalf of the owner, of the copyrighted work described.
capcha
Download Presentation

PowerPoint Slideshow about ' Advanced Chemistry Notes' - dian


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.While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server.


- - - - - - - - - - - - - - - - - - - - - - - - - - E N D - - - - - - - - - - - - - - - - - - - - - - - - - -
Presentation Transcript
Advanced chemistry notes

Advanced Chemistry Notes

Solution Notes


Solutions
Solutions

Solutions – homogeneous mixtures of two or more substances

  • Made up of:

    • Solvent – substance that does the dissolving

    • Solute – substance being dissolved

  • Examples of Solutions

    • Kool-Aide: water – solvent, sugar – solute

    • Pop: water – solvent, carbon dioxide – solute


Solutions1
Solutions

Types of Solutions

  • Liquid – Solid solution

    • Ex: salt water

  • Liquid – Liquid solution

    • Ex: hydrochloric acid and water

      • Miscible – when two liquids mix

      • Immiscible – when two liquids will not mix

  • Liquid – Gas solution

    • Ex: oxygen and water


Solutions2
Solutions

Other types of Solutions

  • Solid – Solid solutions

    • Brass alloys

  • Solid - Liquid solutions

    • Gold dissolves Mercury

  • Solid – gas solutions

    • Palladium dissolves hydrogen

  • Gas – Gas solution

    • air: O2, N2, Ar


Creating solutions
Creating Solutions

The dissolving process consists of three steps

  • Dissociation

  • Solvation

  • Diffusion


The dissolving process
The Dissolving Process

The Dissolving Process(Ex: sugar and water)

1. Dissociation

  • Attractive forces between solute molecules must be overcome.

  • Water pulls sugar apart molecule by molecule


The dissolving process1
The Dissolving Process

2. Solvation

  • Positive ends of solvent molecule attach to negative ends of solute molecule and vise versa.

  • Water molecules surround and interact with sugar molecules.

  • Water molecules remove sugar molecules from the crystal

    • Dispersion and dipole forces are at work here




The dissolving process3
The Dissolving Process

  • When the solvent is water the solvation process is called hydration.


The dissolving process4
The Dissolving Process

3. Diffusion

  • Random molecular movement spreads solute through out the solution

  • Sugar molecules are evenly dispersed throughout the water


Factors influencing dissolving
Factors Influencing Dissolving

  • Factors that influence that rate at which a substance dissolves

    • Temperature

    • Stirring

    • Large surface area of solute exposed to solvent

  • How does this relate to putting sugar in your coffee?


Solvent selectivity
Solvent Selectivity

What will and will not dissolve?

  • G R of T Like dissolves Like

  • Polar substances dissolves other polar substances

    • Polar – ionic and polar covalently bonded compounds have dipoles

      • H2O and HCl


Solvent selectivity1
Solvent Selectivity

  • Non-polar substances dissolve other non-polar substances

    • Non-polar compounds lack dipoles

      • CO2 and N2

      • Oil and Soap

  • Exceptions to the rule

    • Chalk (CaCO3) does not dissolve in water –Why? Both are polar.

      • Water has to be able to overcome chalks (CaCO3) intermolecular attractive forces to dissolve it – it can’t

      • Chalk (CaCO3) is to tightly bonded intermolecularly


Solubility
Solubility

  • How much solute can a substance hold?

  • Unsaturated solution – the solvent could dissolve more solute under standard conditions


Solubility1
Solubility

  • Saturated solution – when solvent can hold no more solute at a given temperature.

    • When solution is saturated some of the solute remains at the bottom of the glass. Dissolving and precipitating occur at equal rates. This is called Dynamic Equilibrium.

    • H2O(l) + NaCl(s) == Na+(aq) + Cl-(aq)


Solubility2
Solubility

  • Supersaturated – solution holds more solute than it would at standard conditions


Solubility3
Solubility

Temperature and Solubility

  • When temperature is increased solubility also increases

  • Consider the endothermic reaction below (solid dissolved in liquid)

    KClO3(s) + H2O(l) + heat == K+(aq) + ClO3-(aq)

    • Heat acts as a reactant (needs heat to dissolve)

  • Adding heat increases solubility  makes more solution



Solubility5
Solubility

Temperature and Solubility

  • When temperature is increased solubility decreases

  • Consider the exothermic reaction below (liquid dissolves a gas)

    CO2(g) + H2O(l) == Heat + CO2(aq)

    • Heat acts as a product (gives off heat)

  • Adding heat decreases solubility

    • What holds more carbonation – warm or cold pop?


Solubility6
Solubility

Pressure and Solubility

  • Effects of pressure on the solubility of liquids and solids are minimal.

  • Effects of pressure on the solubility of gases are drastic.

    • Henry’s Law – the solubility of gases increases with the partial pressure of gases above the solution.

      • EX: Pop – when you open a can of pop the result is the carbon dioxide escaping from the solution because the partial pressure of the gases above the pop decreases.



Solutions3
Solutions

Summary

  • Components of a solution

  • The dissolving process

    • Factors affecting dissolving Process

  • Solvent Selectivity

  • Solubility

    • Unsaturated / saturated /supersaturated

    • Temperature / Pressure


ad