IMPROVING PERFORMANCE IN CHEMISTRY

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IMPROVING PERFORMANCE IN CHEMISTRY

• UCE CHEMISTRY
• BY
• MR. OTIM EMMANUEL
• TEACHER OF CHEMISTRY
• MAKERERE COLLEGE SCHOOL

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TESTABLE OBJECTIVES IN CHEMISTRY

• KNOWLEDGE
• Knowledge of chemical terminology and
  conventions.
• Knowledge of a variety of experimental methods
  from work in the laboratory, from demonstrations
  that provide experience of techniques, of
  equipment and of observation.
• Knowledge of the main facts that have been
  established.
• Knowledge of the main generalizations that have
  been made and of the theories that are widely
  held.
• N.B. Abilities tested here include recall,
  state, recognise, name and define,

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COMPREHENSION, APPLICATION AND EVALUATION

• The ability to understand and interpret
  scientific information presented in verbal,
  numerical or graphical form and to translate such
  information from one form to another.
• The ability to explain familiar phenomena in
  terms of relevant models, laws and principles.
• The ability to select and apply known laws and
  principles to given situations.

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CONTD

• The ability to analyse given data.
• The ability to recongise mistakes and
  misconceptions.
• N.B. Abilities tested here include explain,
  interpret, predict, judge and classify.

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PRACTICAL ABILITIES

• The ability to apply the above knowledge and
  abilities to practical situations.
• The ability to handle apparatus and perform
  experiments in given situations.
• The ability to make accurate observations.
• The ability to devise simple experiments.
• The ability to record results accurately and
  present data in an appropriate form.
• The ability to make correct deductions from
  observations.

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EXAMINATION FORMAT

• 545/1 PAPER 1 50 OBJECTIVE TYPE QUESTIONS 1 ½
  HOURS 50 MARKS
• 545/2 PAPER 2 SECTION A 10 COMPULSORY QUESTIONS
  SECTION B 4 ESSAY TYPE QUAETIONS 2 HOURS 80 MARKS
• 545/3/4/5 PRACTICAL PAPER 2 HOURS 30 MARKS
• THE MARKS ARE SCALED DOWN TO 25, 50 25.

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545/3/4/5 PRACTICAL PAPER

• Write the correct pipette value correctly i.e.
  10.0 cm3 or 20.0 cm3 or 25.0 cm3.
• Fill the table of values to two decimal places
  e.g. 22.50 cm3 and subtract values correctly.
• Select at least two titre values to be used for
  calculating the average titre value.
• Calculate the required variable from First
  Principles.
• Where a thermometer is used enter the correct
  readings in the table to 1 decimal place.
• For qualitative analysis, teach students to
  follow instructions properly, make observations
  and draw correct deductions from their
  observations. They should test gases such as
  carbon dioxide, ammonia, hydrogen chloride,
  sulphur dioxide correctly. Correct use of
  chemical terms and writing formulae of cations
  and anions must be emphasized.

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WHY POOR PERFORMANCE IN CHEMISTRY?

• Attitude of the students.
• Methodology i.e. handling of the subject.
• Survival trend (time).
• Inadequate feedback from examining body.
• Lack of chemicals and apparatus.
• Motivation of students and teachers.

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DETAILED CAUSES OF FAILURE

• Poor writing of chemical names e.g. carbondioxide
  
• Using trivial names or trade names such as marble
  chips, quick lime, lime water etc
• Mis-spelling words e.g. consentrated, involved
  etc. Poor English especially in essay
  (descriptive) questions.
• Mixing up names e.g. magnesium oxide instead of
  manganese(IV) oxide
• Not using correct oxidation state or valency for
  elements with more than one oxidation state or
  valency such as copper oxide instead of
  copper(II) oxide.

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Causes continued

• Using symbols or formulae in descriptive work.
• Using un-conventional words such as ppt, excs, c,
  conc., etc.
• Giving more responses than required. For example,
  give two uses of hydrogen.
• Equations Wrongly written equations do not get
  any marks awarded.
• Using wrong symbols e.g. CL, AL, CU, Ca, mg, pb,
  fe, k and Zn
• Using wrong formulae e.g. Co2, Co, NaoH, H2o etc.
• Not indicating conditions for reactions, i.e.
  heat.

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Causes continued

• In practical work, using words that are ambiguous
  such as clear solution, white solution, reacts,
  carbon dioxide
• Failure to relate knowledge gained in practical
  work, if any, to questions set in theory.
• Grammatical errors e.g. election (electron),
  rather (lather), iron (ion), cell (shell) etc.
• Graphs with un-labelled axes, poor scale, poorly
  plotted and joined points. Instructions are not
  followed.

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Causes continued

• Wrongly written structural formulae.
• Using prepared formulae e.g. molarity
  concentration in g per litre/formula mass.
• Using units in wrong places e.g. RAM, RMM, RFM.
• Poor mathematical background.
• Not sticking to accuracy level indicated in the
  stem of the question e.g. 12.4 g
• Poor interpretation of the mole concept.
• Drawing diagrams that are not to scale are not
  properly labelled. The apparatus used is NOT
  working.

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WAY FORWARD 1 Key Words

• Classify is to group or arrange items according
  to their behavior (system/category/Principle)
  e.g. oxides
• Explain is to make an issue clear or
  understandable, giving reasons or the difference.
• Identify or state or list or outline
• When these words are used in a question, one can
  use a symbol/formula or name but not both e.g.
  identify a gas that re-lights a glowing splint.
  The answer is either oxygen or O2 but not oxygen
  (O2).
• Deduce is to infer/conclude by logical
  reasoning. This is commonly examined in all
  papers but more so in paper 3.
• Define is to set boundaries of or determine
  something.

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WAY FORWARD 2

• Describe is expecting one to explain or write
  about or give a detailed account of something.
  Picture something and write about it in details.
• Discuss is to write about something
  deliberately. You consider and argue about the
  positive and negative aspects of the topic or
  idea or statement made. This is very rare in
  chemistry.
• Illustrate is to make something clear or easily
  understood by examples or comparisons.

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WAY FORWARD 3

• Examine children on low ability skill questions
  e.g. state, identify, mention, outline etc and
  high ability skill questions e.g. explain,
  describe etc.
• Teach chemistry by practical approach (Learner
  Centered) as much as possible. Where the learner
  centered approach does not work, demonstrate
  otherwise minimize use of chalk talk method.
• Interest students in mathematics so that they can
  appreciate the obvious importance of mathematics
  in chemistry.

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WAY FORWARD 4

• Think of unique practical questions that are
  challenging to students to give them opportunity
  to think critically. Give practical work as
  frequently as possible.
• Your students should endeavour at all times to
  comprehend/understand the questions before
  answering them.
• Test students more in paper 2. Try to set your
  own questions following the normal patterns in
  paper 2.

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WAY FORWARD 5

• Encourage students to
• Use correct grammar and chemical terms in their
  work. They should not misuse words.
• Use chemical names than trade names or trivial
  names.
• Use proper words and not abbreviations e.g. ppt,
  conc, xcs etc.
• Describe or explain using words and not symbols
  or formulae. Train students to acquire reasoning
  capacity so as to be able to explain facts in
  chemistry.
• Write correct symbols and formulae.
• Write well balanced chemical equations with
  correct state symbols and indicate conditions of
  reactions. Equations constitute unavoidable
  language of chemists.

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WAY FORWARD 6

• Write correct structural formulae for organic
  compounds.
• Write names of compounds with variable oxidation
  states or valencies using Roman numbers in
  brackets e.g. iron(III) chloride, lead(II) oxide
  etc.
• Write names of compounds correctly e.g.
  copper(II) sulphate, carbon monoxide etc.
• Use units appropriately (RMM or RFM or RAM do not
  require units).
• Draw representative graphs with axes labeled,
  scale given, and points correctly plotted and
  smoothly joined.
• Draw diagrams with working apparatus to scale and
  label them appropriately using names of reagents,
  gases etc. Instill skills of drawing diagrams in
  science.

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WAY FORWARD 7

• Calculate from First Principles, observe accuracy
  and avoid using prepared formulae as much as
  possible.
• Interpret molarity well.
• Record observations in practical work using
  acceptable words and make critical conclusions.
• BELIEVE IN YOUR SELF, YOUR ABILITY TRUST IN
  OTHERS GUIDANCE (WISE COUNSEL)
• GOOD LUCK