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Le Chatelier’s Principle Lab Step Data Trial 1 Trail 2 (Run up and down the stai

ID: 1015452 • Letter: L

Question

Le Chatelier’s Principle Lab

Step

Data

Trial 1

Trail 2

(Run up and down the stairs)

4

Time (seconds) for color change.

0:36 s

0:23 s

4

Notes for color change

Light orange

Orange

5

Color change (if any) after one (1) drop of dilute ammonia

Change to light pink than pack to orange

Change to light pink than pack to orange

6

Time (seconds) for color change back

None

None

7

Number of drops for color to change back

6 drops

9 drops

1.The equilibrium you were stressing can be written simply like this:Acidic <=> Basic ..Indicate the color associated with each side of the equilibrium.

2.Which way was the equilibrium shifted (right or left) when you blew bubbles

3.Write the balanced chemical equation associated with this. (Hint: Carbonic acid is H2CO3).

4.Which way was the equilibrium shifted when you added the ammonia water?

5.Ammonia water is NH3(aq). Write the balanced chemical equation of the reaction that occurred when you added it.

Step

Data

Trial 1

Trail 2

(Run up and down the stairs)

4

Time (seconds) for color change.

0:36 s

0:23 s

4

Notes for color change

Light orange

Orange

5

Color change (if any) after one (1) drop of dilute ammonia

Change to light pink than pack to orange

Change to light pink than pack to orange

6

Time (seconds) for color change back

None

None

7

Number of drops for color to change back

6 drops

9 drops

Explanation / Answer

For the reaction shown above.

1. Acidic <==> Basic

Color associated with each side, acidic phenol red solution has a yellow color or light orange color whereas, basic phenol red solution has a darker reddish or orange color.

2. The equilibrium shifts towards left handside when we blew bubbles. We are introducing CO2 into the solution by bubbling.

3. Balanced equation,

H2O + CO2(bubbles) <==> H2CO3 which dissociates as,

H2CO3 <==> H+ + HCO3-

So we get more H+ in solution

4. The equilibrim shifts towards right handside when we add NH3 water to the solution.

5. Balanced equation,

NH3 + H2O <==> NH4+ + OH-

So more OH- generated in the system shifts equilinbrium towards right handside.