some basics of Ions in solution in which devided by two aspects one is the solution aspect and second one is ionic

1. Ions in solution
Ibrahim Khalil
(Haji)
001BS(CHEM)15

2. SYNOPSIS
• Previous concept about the ionic compounds
• Modern concept of ionic compound
• Solution
• Concentration of solution
• Types of solution
• Ionic aspect of solution
• Migration of ions
• Experimental view
• Applications

3. Previous concept about the compounds
• Early ideas of atoms and compounds, developed primarily through the reactions of
solids and gases, did not include the concept of charge. Atoms and molecules were
seen as neutral particles. However, as the study of chemistry progressed to include
sols, new models were needed because the old models could not explain electrical
conductivity.
• Solutions of compounds like sugar did not increase the electrical conductivity of
water, yet they had lower freezing points than pure water.
• Solutions of compounds such as sodium chloride greatly affected the electrical
conductivity of water, and they also caused the freezing point of the solution to be
reduced twice as much as was observed in sugar water solutions.

4. Modern concept of compound
• A new model that explained these observations was based on the
concept that charged particles, which were called ions, formed in
solutions. If compounds like sodium chloride broke apart into charged
particles when in solution, the ions could carry electrical current.
Substances such as sugar must not break into ions in solution because
they did not conduct electricity. These studies of the characteristics of
solutions led to a more complete and accurate understanding of
chemistry at the particulate level.

5. Solution:
A solution is a homogeneous mixture of two or more substances on
molecular level. The constituent of the mixture present in a smaller
amount is called the Solute and the one present in a larger amount is
called the Solvent. For example, when a smaller amount of sugar
(solute) is mixed with water (solvent), a homogeneous solution in
water is obtained. In this solution, sugar molecules are uniformly
dispersed in molecules of water. Similarly, a solution of salt (Na+ Cl–) in
water consists of ions of salt (Na+,Cl–) dispersed in water.

6. CONCENTRATION OF A SOLUTION
• The concentration of a solution is defined as the amount of solute present
in a given amount of solution.
• Expressing the concentration as:
• A solution containing a relatively
low concentration of solute is called
Dilute solution.
• A solution of high concentration is
called Concentrated solution.

7. Types Of Solution
• The common solutions that we come across are those where the solute is a solid
and the solvent is a liquid. In fact, substance in any three states of matter (solid,
liquid, gas) can act as solute or solvent. Thus there are seven types of solutions

9. Ionic Aspect Of Solution
• Savante Arrhenius studied the conduction of current through water
solutions of electrolytes. He came to believe that the conductivity of
solutions was due to the presence of ions. In 1884, Arrhenius put
forward his theory of ionisation. Arrhenius theory of ionisation may
be stated as:
• (1) When dissolved in water, neutral electrolyte molecules
are split up into two types of charged particles. These particles
were called ions and the process was termed ionisation. The
positively charged particles were called cations and those having
negative charge were called anions.

10. MIGRATION OF IONS
• We know that electrolytes dissociate in solution to form positive ions
(cations) and negative ions (anions).

11. Experimental view
• As the current is passed between the electrodes of the electrolytic cell, the ions
migrate to the opposite electrodes.
Thus in the electrolytic solution of AgNO3,
the cations (Ag+) will move to the cathode
and anions (–3 NO) will move to the anode.
Usually different ions move with different rates.
The migration of ions through the electrolytic
solution can be demonstrated by the following
experiments.

12. Application
• Adsorption
• Colloids
• Batteries
• Etc

13. ?