Electrolytes And Non-electrolytes Case Solution
Notes:
- Ionic species that remain in solution on both sides of the ionic equation are known as spectator ions and essentially do not participate in the overall reaction which is primarily the net ionic equation.
- Balance the equation in its standard or molecular form and use these coefficients in the ionic and net ionic equations.
- When writing the ionic and net ionic equations the correct charge on every separated ion must be included.
PROCEDURE
- Electrolytes and Non-electrolytes
Using the conductivity meter, record the reading for each of the substances and mixtures listed on Data Sheet 1. Make all measurements in 30- or 50 mL beakers. Always rinse the electrodes of the conductivity meter and all reaction containers with distilled water. Ensure that all flasks are completely dried before measuring the conductivity of any solid material. Use approximately 15 mL of each liquid. While stirring with electrodes, press the high scale setting on the meter (if applicable) and record the conductivity.
From the conductivity meter:
A reading of zero indicates non-conductive
A reading of one through seven indicates weak to moderate conductivity
A reading greater than seven indicates strong conductivity.
Next to the conductivity reading on your data sheet, indicate the specific ions or molecules that gave rise to the observed reading. In the last column, explain the source of these ions and/or molecules (for example, the complete, partial or absence of ionization of a covalent compound in water).
- Typical Ionic Reactions
You will experiment with a number of ionic type reactions to determine their essential nature. By conductivity tests of the separate reactants and the mixture after reaction, discover whether the acids, bases and salts are highly conductive, weak to moderate conductive or non-conductive.
- While stirring with the electrodes, carefully pour the 0.1M HCl solution into the 0.1M NaOH solution. Measure and record the conductivity of the products of the reaction.
- Measure the conductivity of the 15 mL sample of 0.1M H2SO4 and 0.1MBa(OH)2 solutions separately. Add one or two drops of phenomenological to the acid solution. While stirring with the electrodes, carefully pour the base solution into the acid solution (slowly). Add more base slowly until a permanent faint pink end-point is reached. Measure and record the conductivity of the products of the reaction (at the end-point).
- While stirring with the electrodes, carefully pour the 0.1M HC2H3O2 (acetic acid) solution into the 0.1M NH4OH solution. Measure and record the conductivity of the products of the reaction.
Using the data collected in Part II, write the ionic and net ionic equations for each of these reactions.
DATA SHEET 1
Name:_________________________________________ Date:_____________________
| Sample to be Tested | Meter reading | Ions or molecules causing conductivity or non-conductivity (be specific where possible) | Reasons for the presence of these ions or molecules |
| 1. Tap water
|
2
|
conductivity |
The most abundant cations present in water are calcium (Ca), magnesium (Mg), sodium (Na), and potassium (K) |
| 2. Distilled water
(pure covalent) |
0
|
Non conductivity |
Distillation kills most organic matter and removes minerals from the water |
| 3. 0.10M NaOH
(strong base) |
8
|
Non-conductivity | It is used for different analysis and it will not conduct electricity |
| 4. 0.10M NH4OH
(weak base) |
4
|
Conductivity | It completely ionize in water and are a good conductor of electricity |
| 5. 0.1M HC2H3O2
(acetic acid, a weak acid) |
4
|
Non-conductive | They are weak electrolyte |
| 6. Water solution of sucrose (C12H22O11)
(pure covalent) |
0
|
Non-conductive | They having a few ions to carry charge |
| 7. Solid NaCl (ionic)
Flask must be dry – cover base of electrode with solid. |
0
|
Non-conductive | They have no electrons which are free to move |
| 8. NaCl(aq)
Add enough water to the solid from #7 to form a solution. |
12
|
Conductive | When in solution it dissociates into Na+ and Cl-. When you put electrodes in the solution, the cations are drawn to the cathode and the anions to the anode |
| 9. 0.10MHCl(aq)
(strong acid) |
10
|
Conductive | Because it forms ions |
DATA SHEET 2
Name:______________________________________________ Date:__________________
TYPICAL IONIC REACTIONS
2a. 0.1M HCl(aq) with 0.1M NaOH(aq). (Meter Reading)
| HCl(aq):
10 |
NaOH(aq):
8 |
Mixture:
11 |
| Total ionic equation for reaction:
Na+(aq) + OH-(aq) +H+(aq) + Cl-(aq)à Na+(aq) + Cl-(aq) + H2O(1)
|
||
| Net ionic equation for reaction:
H+(aq) + OH-(aq)à H2O(1) |
||
2b. 0.1M H2SO4(aq) with 0.1M Ba(OH)2(aq). (Meter Reading)
| H2SO4(aq):
9 |
Ba(OH)2(aq):
8 |
Conductivity at end-point:
2 |
| Total ionic equation for reaction:
Ba2+(aq) + 2OH-(aq) + 2H+(aq) + SO42+(aq)à2H2O(L) + BaSO4(s) |
||
| Net ionic equation for reaction:
Ba2+(aq) + 2OH-(aq) + 2H+(aq) + SO42+(aq)à2H2O(L) + BaSO4(s) This reaction is both a neutralization reaction and a precipitation reaction then both equation are same. |
||
2c. 0.1M HC2H3O2(aq) with 0.1M NH4OH(aq). (Meter Reading)
| HC2H3O2(aq):
4 |
NH4OH(aq):
4 |
Mixture:
8 |
| Total ionic equation for reaction:
H+(aq) + C2H3O2-(aq) + NH4-(aq) + OH-(aq)à NH4+(aq) + C2H3O2-(aq) + H2O(I) |
||
| Net ionic equation for reaction:
H+ (aq) + OH-(aq)à H2O(I) |
||
Name:___________________________________________________ Date:_______________
POST LAB
In the space provided, write the balanced IONIC and NET IONIC equation.
- (NH4)2SO4 +2KOH -->2NH4OH + K2SO4
ionic, sol. ionic, sol. w. elect. ionic, sol.
| IONIC: (NH4)2SO4 (aq) + 2KOH (aq) à2NH3(g) + 2H2O (l) + K2SO4 (aq)
2NH4- SO42- 2K+ 2OH-à 2NH3 2H2O 2K+SO42-
|
| NET IONIC:
2NH4- (aq) + 2OH-(aq) à 2NH3 (g) + 2H2O (l) NH4+ (aq) + OH-(aq) à NH3(g) + H2O (l)
|
- BaCl2 + Na2CO3 --->2NaCl + BaCO3
Ionic, sol. ionic, sol. ionic, sol. ionic, insol.
| IONIC:
2Na+(aq) + CO32-(aq) + Ba2+(aq) + 2Cl1(aq)à 2Na1+(aq) + 2Cl1(aq) + BaCO3(s)
|
| NET IONIC:
Ba2+ (aq) + CO32- (aq)à BaCO3 (s)
|
- 3HNO3 + Al(OH)3 --->3H2O + Al(NO3)3
Str. elect. ionic, insol. ionic, sol.
| IONIC:
3H+ + 3NO3- + Al(OH)3à Al3+ + 3NO3- + 3H2O
|
| NET IONIC:
3H+(aq) + Al(OH)3 (s)à Al3+(aq) + 3H2O(l) |
- 2HCl + Mg(C2H3O2)2 ---> MgCl2 + 2HC2H3O2
Str. Elect. ionic, sol. ionic, sol. wk. Elect.
| IONIC:
2H+ + 2Cl- + Mg2+ + 2C2H3O2-à Mg2+ + 2Cl- + 2HC2H3O2 |
| NET IONIC:
2H+ + Mg2+ + 2C2H3O2-à Mg2+ + 2HC2H3O2 |
- NH4OH + HC2H3O2 ---> H2O + NH4C2H3O2
Wk. Elect. wk. Elect. ionic, sol.
| IONIC:
NH4+ (aq) + OH- (aq) + HC2H3O2 (aq)à H2O(l) + NH4+ (aq) + C2H3O2-(aq) |
| NET IONIC:
OH- (aq) + HC2H3O2 (aq)à H2O(l) + C2H3O2-(aq) |
...............
This is just a sample partial case solution. Please place the order on the website to order your own originally done case solution.
