Two Lab Reports

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Student
Name

Mohammed Alnaimi

Student ID 48408
Lesson Equilibrium and Le Châtelier’s Principle
Institution Ocean County College
Session 2019L3 CHEM 182 DL1
Course CHEM 182 DL1
Instructor Nancy Marashi

Final Report

Exercise 1

CHEM 182 DL1
Equilibrium and Le Châtelier’s Principle

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T he Reaction is Endothermic because the substance became more acidic which
equals to higher heat energy.

1. Use your results to determine if the forward reaction in the potassium chromate/HCl
reaction endothermic or exothermic. Explain your answer, using the table below to help
construct your thoughts.

K=(Cr2 O7)(H20)(KCl)2 / (K2 CrO4) (HCL)2

2. Write the equation for the equilibrium constant (K) of the reaction studied in this
exercise.

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Data Table 1: Chromate and Dichromate

Q=1.6 * 10 (-10 exponent)

Use this information to answer Questions 3, 4, and 5:

The equilibrium constant (K) of the reaction below is K = 6.0 x 10 , with initial concentrations as
follows:

[H ] = 1.0 x 10 M, [N ] = 4.0 M, and [NH ] = 1.0 x 10 M.

3. Consider the chemical reaction: N + 3H yields 2NH . If the concentration of the
reactant H was increased f rom 1.0 x 10 M to 2.5 x 10 M, calculate the reaction
quotient (Q) and determine which way the chemical system would shif t by comparing the
value of Q to K.

-2

2 -2 2 3 -4

2 2 3
2 -2 -1

Q=1.270131585632272 * 10 (2 exponent) It will shif t lef t.

4. If the concentration of the reactant H was decreased f rom 1.0 x 10 M to 2.7 x 10 M,
calculate the reaction quotient (Q) and determine which way the chemical system would
shif t by comparing the value of Q to K.

2 -2 -4

Q=7.84 * 10(-4 exponent). It will shif t right.

5. If the concentration of the product NH was increased f rom 1.0 x 10 M to 5.6 x 10 M,
calculate the reaction quotient (Q) and determine which way the chemical system would
shif t by comparing the value of Q to K.

3 -4 -3

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Data Table 2: Endothermic & Exothermic Equilibrium Position

Color of Chromate Color of Dichromate

Color of Chromate Number of Drops of NaOH to Shift Equilibrium Position

Dark yellow Orange

Dark yellow 7

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Exercise 2

Reaction at Room Temperature

Color

Chemical System Shift (Left or
Right)

Explanation of why chemical
system is shifted to the left or
to the right

Reaction in Cold Water Bath

Color

Chemical System Shift (Left or
Right)

Explanation of why chemical
system is shifted to the left or to
the right

Reaction in Hot Water Bath

Color

Chemical System Shift (Left or
Right)

Explanation of why chemical
system is shifted to the left or to
the right

Red Orange

Bright Orange

Left- towards the
reactants

There were solid
particles on the bottom
of the pipet while the
liquid maintained the
majority of the pipet. So
there was a solid potion
and liquid potion. potion.

Red-Orange

Right-Towards the
products

The solution was all
liquid, so there were no
solid particles. This
means the reactants
mixed together formed
the product.

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Data Table 3: Ferric Ferrocyanide

The equilibrium position would shift left because the product ratio increases when NaOH is added.

1. From your observations and data collected in Data Table 3, describe the direction of
the equilibrium posit ion shif t upon addit ion of NaOH.

Color of Potassium Ferrocyanide Color of Ferric Ferrocyanide

Color of Potassium
Ferrocyanide

Number of Drops of NaOH to Shift Equilibrium Position

Color of Potassium
Ferrocyanide

Observations when Equilibrium is Shifted

Light yellow Dark blue/greenish

Light yellow 4 drops

Light yellow The dark blue/greenish
substance turned brown
while the surrounding
substance turned
yellow.