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    Basic Analytical Chemistry

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    HARIS KHAN

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    © All Rights Reserved
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    Basic Analytical Chemistry

    Uploaded by

    HARIS KHAN
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    2 views7 pages

    Basic Analytical Chemistry

    Uploaded by

    HARIS KHAN

    Copyright:

    © All Rights Reserved
    Download as PDF, TXT or read online from Scribd
    Download as pdf or txt
    of 7

    OA

    SIS O GE
    F KNOWLED

    JARAMOGI OGINGA ODINGA UNIVERSITY OF SCIENCE AND


    TECHNOLOGY
    SCHOOL OF BIOLOGICAL AND PHYSICAL SCIENCES
    UNIVERSITY EXAMINATION FOR THEDEGREE OF BACHELOR OF
    EDUCATION (SCIENCE)
    1ST YEAR 2ND SEMESTER 2016/17

    MAIN REGULAR

    COURSE CODE: SCH 104

    COURSE TITLE: BASIC ANALYTICAL CHEMISTRY

    EXAM VENUE: STREAM: (BED SCI)

    DATE: EXAM SESSION: 2.00 – 4.00 PM

    TIME: 2:00HRS
    _______________________________________________________________________________
    ______
    Instructions:
    1. Answer question 1 (Compulsory) in Section A and ANY other 2 questions in
    Section B.
    2. Candidates are advised not to write on the question paper.
    3. Candidates must hand in their answer booklets to the invigilator while in the
    examination room

    1
    SCH 104: Basic Analytical Chemistry
    MAIN EXAMINATION
    Time: 2 Hours
    Section A
    Answer All Questions in Section A
    Question 1

    a) Analytical chemistry is the study of separation, identification and


    quantification of chemical components in natural and artificial
    materials. Briefly describe two major industrial or societal fields where
    the concepts of analytical chemistry can be applied. (4 marks)
    b) Define the terms:
    i. Population
    ii. Sample
    iii. Analyte
    iv. qualitative analysis
    v. quantitative analysis
    vi. Data Analysis
    (6 mark)
    c) What are some of the wet chemistry methods employed in sample
    identification and quantification? (3 marks)
    d) Use the diagram below to differentiate between accuracy and precision
    in sample quantification. (4 marks)

    2
    e) A measuring balance is precise to a gram. A student gave the following
    wrong readings. Please correct them.
    i. 12.300 g;
    ii. 0.004 g;
    iii. 120.0008 g;
    iv. 1100 g (4 marks)

    f) Titanium carbide, TiC, is the hardest of the known metal carbides. It


    can be made by heating titanium(IV)oxide, TiO2, with carbon black to
    2200 °C. TiO2 + 3C → TiC + 2CO
    i. What is the maximum mass of titanium carbide, TiC, that can be
    formed from the reaction of 985 kg of titanium(IV)oxide, TiO 2,
    with 500 kg of carbon, C? (2 marks)
    ii. Identify the reagent in excess? (2 marks)
    g. Phosphorus tribromide, PBr3, can be used to add bromine atoms to
    alcohol molecules such as 2-methyl-1-propanol. In an experiment,
    5.393 g of 1-bromo-2-methylpropane form when an excess of PBr3
    reacts with 6.034 g of 2-methyl-1-propanol. Determine the percent
    yield using the given reaction stoichiometry equation. (5 marks)
    3CH3CH(CH3)2CH2OH + PBr3 → 3CH3CH(CH3)2CH2Br + H3PO3
    2-methyl-1-propanol 1-bromo-2-methylpropane

    3
    Section B
    Answer any Two Questions
    Question 2
    Briefly describe the qualitative and/or quantitative data obtained using the
    following analytical instruments. Discuss the physical quantity employed by
    the machines. (20 marks)
    a. Flame Emission Spectrometry
    b. Atomic Fluorescence Spectrometry
    c. Visible and Ultraviolet Spectrometry
    d. Nuclear Magnetic Resonance (NMR) Spectrometry
    e. Mass Spectrometry

    Question 3
    a. Briefly describe how you would prepare 16 ppm of Lead (II) ions in
    the laboratory using Lead (II) Chloride salt. (4 marks)
    b. Using examples, distinguish between the following chemical reactions
    i. Direct combination or synthesis
    ii. Single displacement or substitution,
    iii. Metathesis or double displacement reaction
    iv. Acid-base reactions
    v. Redox reactions
    (10 marks)
    c. Water is a universal solvent and there are several reactions that take
    place in aqueous medium. Discuss some of the useful Chemical
    reactions that take place in water under the following processes.
    i. Dissolving Insoluble Compounds

    4
    ii. Synthesis of Inorganic Compounds
    iii. Extraction of Metals from Solution
    (6 marks)
    Question 4
    The diagram below shows different stages an Analytical Chemist undertakes
    to accomplish the task at hand. Briefly describe the stages labeled 1 to 5
    under the following subtopics.
    i. Instruments
    ii. Methods
    iii. Standards
    (20 marks)

    5
    Question 5
    Separation of a sample into different analytes and subsequent data acquisition
    from the analyte can be done using classical methods or instrumental
    methods. Briefly explain the working mechanisms of the following classical
    and instrumental methods.
    i. Precipitation
    ii. Solvent extraction
    iii. Titration
    iv. Column Chromatography
    v. Ultra-violet spectrometer
    vi. High Performance Liquid Chromatography
    vii. Gas Chromatography-Mass spectrometer

    6
    7

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