Chemistry Laboratory Manual DK014

DK014 Lab Manual
July 12, 2021

DK014 Lab Manual

MATRICULATION DIVISION
MINISTRY OF EDUCATION MALAYSIA

CHEMISTRY

LABORATORY MANUAL
SEMESTER I
DK014

2021

TWO YEAR
MATRICULATION PROGRAMME

FOURTH EDITION

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DK014 Lab Manual

NATIONAL EDUCATION PHILOSOPHY
Education in Malaysia is an on-going effort towards further
developing the potential of individuals in a holistic and integrated
manner, so as to produce individuals who are intellectually,
spiritually, emotionally and physically balanced and harmonious
based on a firm belief in and devotion to God. Such an effort is
designed to produce Malaysian citizens who are knowledgeable
and competent, who possess high moral standards and who are
responsible and capable of achieving a high level of personal well-
being as well as being able to contribute to the betterment of the
family, society and the nation at large.

NATIONAL SCIENCE EDUCATION PHILOSOPHY
In consonance with the National Education Philosophy, science
education in Malaysia nurtures a science and technology culture
by focusing on the development of individuals who are competitive,
dynamic, robust and resilient and able to master scientific
knowledge and technological competency.

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DK014 Lab Manual

CONTENTS Page
i - ii
Introduction iii - iv
1.0 Learning Outcomes iv
2.0 Laboratory Safety v
3.0 Ethics in the laboratory vi
4.0 Preparation For Experiment
5.0 Report Writing 1

Semester I
Experiment Title

1 Determination Of The Density Of Water

2 Standard Solution And Determination Of The 3
Concentration Of Acid Solution.

3 Quantitative Analysis Of Baking Soda 6

4 Molecular Geometry 9

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INTRODUCTION

1.0 Learning Outcomes

1.1 Matriculation Science Programme Educational Objectives

Upon a year of graduation from the programme, graduates are:

1. Knowledgeable and technically competent in science disciplines
in-line with higher educational institution requirement.

2. Able to communicate competently and collaborate effectively in group
work to compete in higher education environment.

3. Able to solve scientific and mathematical problems innovatively and
creatively.

4. Able to engage in life-long learning with strong commitment to continue
the acquisition of new knowledge and skills.

1.2 Matriculation Science Programme Learning Outcomes

At the end of the programme, students should be able to:

1. Acquire knowledge of science and mathematics fundamental in higher
level education.
(PEO 1, MQF LOD 1)

2. Demonstrate manipulative skills in laboratory work.
(PEO 1, MQF LOD 2)

3. Communicate competently and collaborate effectively in group work
with skills needed for admission in higher education institutions.
(PEO 2, MQF LOD 5)

4. Apply logical, analytical and critical thinking in scientific studies and
problem solving.
(PEO 3, MQF LOD 6)

5. Independently seek and share information related to science and
mathematics.
(PEO 4, MQF LOD 7)

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1.3 Course Learning Outcome

13.1 Chemistry 1

At the end of the course, student should be able to:
1. Explain basic concepts and principles of physical chemistry in novel

and real life situations.
(C2, PLO1, MQF LOD1)

2. Demonstrate the correct techniques in handling laboratory
apparatus and chemicals when carrying out experiments.
(P4, PLO2, MQF LOD2)

3. Discuss in group the understanding of knowledge and concept in
physical chemistry. (C3, P3, PLO3, A2, CTPS3, LOD5)

4. Solve chemistry related problems by applying the basic concepts
and Principles in physical chemistry.
(C3, PLO4, CTPS3, MQF LOD 6)

1.4 Objectives of Practical Sessions

The main purpose of the experiment is to give the student a better insight of the
concepts of Chemistry discussed in the lectures by carrying out experiments. The
aims of the experiments are to enable students to:
1. learn and practise the necessary safety precautions in the laboratory.

2. plan, understand and carry out the experiment.

3. use the correct techniques in handling the apparatus.

4. acquire scientific skills in measuring, recording and analysing data.

5. observe, measure and record data by giving consideration to the
consistency, accuracy and units of the physical quantities.

6. determine the errors in various physical quantities obtained in the
experiments.

7. deduce logically and critically the conclusion based on observation and
data analysis.

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2.0 Laboratory Safety

The Science Matriculation Programme requires the students to attend practical classes 2
hours a week to complete 4 experiments each semester.

In order for the laboratory to be a safe place to work in, students should learn laboratory rules
and regulations, including the correct way of using laboratory apparatus and handling of
chemicals before starting any experiments.

Laboratory rules and regulations.

1. Attendance is COMPULSORY. If you are unable to attend any practical class, you
should produce a medical certificate or a letter of exemption.

2. Read, understand and plan your experiment before pre-lab sessions and practical
classes.

3. Wear shoes, lab coats and safety goggles at all times in the laboratory.

4. Tie long hair or tuck head scarf under your lab coat

5. Do not wear contact lenses during experiments.

6. Foods and drinks are not allowed in the laboratory.

7. Do not perform any unauthorised experiments! Understand and follow the specified
procedures for each experiment.

8. Do not waste chemicals. Take only sufficient amount of chemicals needed for your
experiments.

9. Replace the lids or stoppers on the reagent bottles or containers immediately after use.

10. Do not remove chemicals from the laboratory.

11. Handle volatile and hazardous compounds in the fume cupboard. Avoid skin contact
with all chemicals, wash off any spillages.

12. Clean up spillages immediately. In case of a mercury spillage, do not touch the
mercury. Notify your instructor immediately.

13. Ensure there are no flames in the vicinity before working with flammable chemicals

14. NEVER leave an ongoing experiment unattended.

15. Be aware or familiar with the location and proper way of handling safety equipment,
including eyewash, safety shower, fire blanket, fire alarm and fire extinguisher.

16. Turn off bunsen flames when not in use. Notify your instructor immediately of any
injury, fire or explosion

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17. Do not throw any solid wastes into the sink. Dispose any organic substances in the
waste bottles provided.

18. Wash all glasswares after use and return the apparatus to its appropriate places.
19. Keep your work area clean and tidy.
20. Notify your instructor immediately of any injury, fire or explosion

I have read and understood the laboratory rules and regulations as stated
above. I agree to abide by all these rules, follow the instructions and act
responsibly at all times.

Signature : Date :

Name : Practicum :

Matric number :

Signature Instructor : Date :

3.0 Ethics in the laboratory

1. Follow the laboratory rules.

2. Students must be punctual for the practical session. Students are not allowed
to leave the laboratory before the practical session ends without permission.

3. Co-operation between members of the group must be encouraged so that each
member can gain experience in handling the apparatus and take part in the
discussions about the results of the experiments.

4. Record the data based on the observations and not based on any assumptions.
If the results obtained are different from the theoretical value, state the possible
reasons.

5. Get help from the instructor or the laboratory assistant should any problems
arise during the practical session.

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4.0 Preparation for experiment

4.1 Pre-lab Sessions.

i. Read and understand the objectives and the theory of the experiment.
ii. Think and plan the working procedures properly for the whole

experiment in a jotter book/science notebook. Make sure you have
appropriate table for the data.
iii. Complete and submit the pre-lab questions provided.

4.2 Practical Sessions
Face to face:
i. Check the apparatus provided.
ii. Conduct the experiment carefully.
iii. Record all measurements and observations made during the
experiment.
iv. Keep the work area clean and tidy.

None face to face:

i. Follow the instructions and video provided by the lecturer.

4.3 Post-lab Sessions

i. Explain what has been carried out and discuss the findings of the
experiment.

ii. Introduce the format of report writing.

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5.0 Report Writing
Follow the instruction given below:

Objective ▪ state clearly
Theory
Procedure ▪ write concisely in your own words
▪ draw and label diagram if necessary
Results/
▪ write in passive sentences about all the
Observation steps taken during the experiment

Discussion ▪ data tabulation with units and
uncertainties
Conclusion
▪ data processing (plotting graph, calculation to
obtain the results of the experiments and its
uncertainties)

▪ give comments about the experimental results
by comparing it with the standard value.

▪ state the source of mistake(s) or error(s) if any
as well as any precaution(s) taken to
overcome them.

▪ answer all the questions given

▪ state briefly the results with reference to
the objectives of the experiment

Reminder: NO PLAGIARISM IS ALLOWED.

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EXPERIMENT 1 DETERMINATION OF THE DENSITY OF WATER

Course Learning Objective

Demonstrate the correct techniques in handling laboratory apparatus and chemicals when
carrying out experiments. (P4, PLO 2, MQF LOD 2)

Learning Outcomes

At the end of this lesson, students should be able to:
i. determine the density of water.
ii. compare the accuracy of the density of water using different apparatus.

Student Learning Time (SLT)
Face-to-face Non face-to-face

2 hour 0

Introduction

Density is defined as mass per unit volume. It is dependent on the temperature. When
temperature increases, the density decreases. Volume of a liquid is measured by using
pipette, measuring cylinder and burette. However, to get accurate volume measurement,
pipette and burette are most commonly used. A top loading balance and an analytical balance
is used to measure mass of a substance. A top loading balance and an analytical balance give
a reading of two and four decimal places respectively.

Apparatus Chemical reagents

Burette
Glass rod
Filter funnel
Beaker (50 mL)
Pipette (10 mL)
Analytical balance
Top loading balance
Measuring cylinder (20 mL)

Procedure

1. Write a procedure on how to determine the density of 10 mL of water using
the apparatus provided.

2. Based on the procedure suggested, determine the density of water.

3. Compare the density of water obtained using different apparatus.

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DATA SHEET

EXPERIMENT 1 DETERMINATION OF THE DENSITY OF WATER

RESULTS

Temperature of water : _________________________
_________________________
Atmospheric pressure: _________________________

Volume of water :

Data Burette Pipette Measuring cylinder
Mass of empty beaker / g
Mass of beaker + water / g
Mass of water transferred / g
Density of water / g mL-1

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EXPERIMENT 2 STANDARD SOLUTION AND DETERMINATION OF THE
CONCENTRATION OF ACID SOLUTION.

Course Learning Objective

Demonstrate the correct techniques in handling laboratory apparatus and chemicals when
carrying out experiments. (P4, PLO 2, MQF LOD 2)

Learning Outcomes

At the end of this lesson, students should be able to:
i. prepare a standard solution of sodium carbonate.
ii. determine the concentration of HCl solution using the standard solution of sodium
carbonate.

Student Learning Time (SLT)
Face-to-face Non face-to-face

2 hour 0

Introduction

A solution of known concentration is called a standard solution. Concentrations are usually
measured as molL-1 or gL-1 . The concentration of a standard solution is often determined by
using a primary standard i.e. a substance that can be accurately weighed and is pure. In its
pure form, the number of moles present can be accurately determined from the measured
weight and its molar mass. In this experiment, pure sodium carbonate is used as a primary
standard to determine the concentration of hydrochloric acid, a secondary standard. An
equivalence point is the point in a titration at which the added titrant reacts completely with
the electrolyte according to stoichiometry. To detect this equivalence point, an indicator which
produces a change in colour is often used. The point at which the indicator changes colour is
called the end point. The end point and equivalence point should ideally be the same.

Apparatus Chemical reagents

Burette Methyl orange
Spatula Distilled water
Glass rod Sodium carbonate, Na2CO3
White tile Hydrochloric acid solution, HCl
Retort stand
Analytical balance
Conical flask (250 mL)
Pipette filler
Filter Funnel
Pipette (25 mL)
Volumetric flask (250 mL)

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Procedure

(A) Preparation of a standard solution
1. Weigh accurately 1.3000 - 1.3500 g of pure sodium carbonate, Na2CO3 , in a clean

dry 50 mL beaker.

2. Add approximately 20 mL of distilled water to dissolve the solid.
3. Carefully transfer the solution into a 250 mL volumetric flask by using a filter funnel.
4. Rinse the beaker with distilled water and pour it into the flask.
5. Add distilled water up to the graduated mark of the volumetric flask.
6. Stopper and shake the flask until the solution is homogeneous.
7. Calculate the concentration of this standard solution.

(B) Standardisation of hydrochloric acid solution
1. Rinse a clean pipette with Na2CO3 solution
2. Pipette 25 mL of Na2CO3 solution into a clean 250 mL conical flask.
3. Add 3 drops of methyl orange as an indicator in the Na2CO3 solution.
4. Rinse a clean burette with HCl solution.
5. Fill the burette with HCl solution. Ensure that no air bubbles are trapped at the tip.
6. Record the initial burette reading to 2 decimal places.
7. Place a piece of white tile underneath the flask.
8. Titrate the Na2CO3 solution with HCl solution. During titration control the stopcock

with your left hand while swirling the conical flask with your right hand.
9. For the first titration, dispense the HCl solution slowly until the yellow solution

changes to orange colour permanently. This is the endpoint.

10. Record the final reading. The difference between the final and initial reading is
gross volume.

11. Repeat the titration 3 times. In the subsequent titrations, dispense the solution
quickly up to a few millilitres from the endpoint. Titrate a drop at a time until the
endpoint is reached.

12. Calculate the concentration of HCl solution.

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DATA SHEET

EXPERIMENT 2 STANDARD SOLUTION AND DETERMINATION OF THE
CONCENTRATION OF ACID SOLUTION.

RESULTS AND CALCULATIONS
(A) Preparation of a standard solution

i. Mass of Na2CO3 = ___________________
ii. Moles of Na2CO3 = ___________________
iii. Molarity of Na2CO3 = ___________________

(B) Standardisation of hydrochloric acid solution

Burette reading / mL Gross I II III
Final reading
Initial reading
Volume of HCl used

Average volume of HCl = ____________mL
Note : Exclude the gross reading in determining the average volume of HCl.
Calculate the molarity of HCl solution.

EXERCISE
Does the addition of water in step 7 (Part B) affect the result of the titration? Explain.

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EXPERIMENT 3 QUANTITATIVE ANALYSIS OF BAKING SODA

Course Learning Objective

Demonstrate the correct techniques in handling laboratory apparatus and chemicals when
carrying out experiments. (P4, PLO 2, MQF LOD 2)

Learning Outcomes

At the end of this lesson, students should be able to:
i. determine the percentage by mass of sodium hydrogen carbonate, NaHCO3, in baking
soda sample.
ii. acquire the correct techniques of titration.

Student Learning Time (SLT)
Face-to-face Non face-to-face

2 hour 0

Introduction

Titration is a laboratory technique used to determine the concentration of a solution using
another solution with a known solution.

Titration also can be used to determine the percentage by mass of the content in any sample
of a solution such as baking soda solution.

Percent by mass is mass of solute in 100 g of solution.

%w/w = mass of solute x 100
mass of solution

Mass of solution can be calculated from the density of baking soda solution which is
1.10gmL-1 at 25 °C

The acid - carbonate reaction is:
Na2CO3 (aq) + 2HCl(aq) 2NaCl(aq) + H2O(l) + CO2 (g)

The reaction can be used to determine the amount of acid that reacts with a known amount of
carbonate. The endpoint is determined using a suitable indicator.

Apparatus Chemical Reagents

Burette Baking soda
Spatula methyl orange
Glass rod Distilled water
White tile Hydrochloric acid solution, HCl (used the same
Retort stand HCl solution prepared in experiment 2
Analytical balance
Conical flask (250 mL)
Pipette filler
Filter Funnel
Pipette (25 mL)
Volumetric flask (250 mL)

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Procedure
1. Weigh accurately 1.4500 - 1.500 g of baking soda sample in a clean dry 50 mL

beaker.
2. Add approximately 20 mL of distilled water into a the beaker. Stir until all solids

are dissolved.
3. Pour the resulting solution into a 250 mL volumetric flask.
4. Rinse the beaker with distilled water and pour it into the flask.
5. Add distilled water up to the graduated mark of the volumetric flask.
6. Stopper and shake the flask until the solution is homogeneous.
7. Pipette 25 mL of this solution into a 250 mL conical flask. Add 2 drops of methyl

orange.
8. Titrate the solution with the standard HCl solution.
9. For the first titration, dispense the HCl solution slowly until the yellow solution

changes to orange colour permanently. This is the endpoint.
10. Record the final reading. The difference between the final and initial reading is

gross volume.
11. Repeat the titration 3 times. In the subsequent titrations, dispense the solution

quickly up to a few millilitres from the endpoint. Titrate a drop at a time until the
endpoint is reached.

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DATA SHEET

EXPERIMENT 3 QUANTITATIVE ANALYSIS OF BAKING SODA

RESULTS
(A) Analysis of baking soda sample

Mass of baking soda (solute) = _____________

Mass of baking soda solution = _____________

Burette reading / mL Gross I II III
Final reading
Initial reading
Volume of HCl used

Average volume of HCl = _____________

CALCULATIONS

1. Calculate the number of mole of HCl needed to react with 25 mL of baking soda
solution.

2. The active constituent of baking soda is sodium hydrogen carbonate NaHCO3. Write
the equation of the reaction between NaHCO3 and HCl.

3. Calculate the number of moles of NaHCO3 in

a) 25 mL of the baking soda solution
b) the original solution in the volumetric flask

4. Calculate the mass of NaHCO3 in the original solution.

5. Calculate the % by mass of NaHCO3. in baking soda.

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EXPERIMENT 4 MOLECULAR GEOMETRY

Course Learning Objective

Demonstrate the correct techniques in handling laboratory apparatus and chemicals when
carrying out experiments. (P4, PLO 2, MQF LOD 2)

Learning Outcomes

At the end of this lesson, students should be able to:
i. view molecules in 3-dimensional structure
ii. determine the shape of molecules using the VSEPR theory

Student Learning Time (SLT)
Face-to-face Non face-to-face

2 hour 0

Introduction

The first step toward visualising the structure of a molecule is to convert its molecular formula
to its Lewis structure. A Lewis structure is a 2-dimensional structural formula that shows how
the atoms are attached to each other within a molecule. It does not reveal the overall shape.
The Valence Shell Electron Pair Repulsion (VSEPR) theory is used to determine the geometry
of a molecule. In the VSEPR theory, the repulsion between two pairs of electrons (i.e. bonding
pairs or lone pairs) in the valence shell is the dominant factor that determines the geometry of
a molecule. The electron pairs around the central atom are oriented as far apart as possible
to reduce the repulsion between them. In this case, the lone pairs repel more strongly than
the bonding pairs.
The geometry of a molecule is determined by the position of the terminal atoms that are
bonded to the central atom. The lone pairs will influence the bond angles but do not contribute
to the shape.

Apparatus

3–D molecular model set (2 students per set)

Procedure
(A) Basic geometry

1. Using a 3-D model set, construct structures with the following geometry:
i. Linear
ii. Trigonal planar
iii. Tetrahedral
iv. Trigonal bipyramidal
v. Octahedral

2. Draw the structures in Table 4.1

3. Determine the bond angles and write the general formulae to represent the
molecules. Use the symbol A as the central atom and X as the terminal atom.

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(B) Molecular geometry
1. Draw Lewis structures and construct the molecular model for the following
molecules:
i. CO2
ii. BH3
iii. CH4
iv. PF5
vi. SF6

2. Draw and name the molecular geometry of each molecule in Table 4.2.

3. State the bond angle(s).

4. Write the general formula of each structure.

EXERCISE

1. What is the most important factor in determining the geometry of a molecule?
2. List down the steps to determine the molecular shape of a compound.

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DATA SHEET

EXPERIMENT 4 MOLECULAR GEOMETRY

TABLE 4.1 Basic Geometrical Drawings And Bond Angles

Molecular geometry Bond angle General formula

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TABLE 4.2 Molecular Geometry and bond angle for particular compounds

compound Lewis structure Molecular Bond angle General formula
CO2 geometry

PH3

CH4

PF5

SF6

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