WWW.SOLUTIONFANS.COM - MASTER OF ALL EXAM RUNS

Home
Stories
News
Edu
Neco Gce 2018 Chemistry Theory and Objective Answers - Nov/Dec Expo - solutionfans.com
   

  • Neco Gce 2018 Chemistry Theory and Objective Answers – Nov/Dec Expo - solutionfans.com
  • Share
    Tweet
    Whatsapp
    Mail

    Chemistry OBJ:
    1-10: DDCACEBCDC
    11-20: EDCEAABCBA
    21-30: EECACEDEAD
    31-40: CBEAECCEDD
    41-50: DDABEDBAEA
    51-60: CECEBACEEA
    ========================

    =====================
    (2)
    Electrolytes are the components that conducts electricity in molten form or in solution e.g Nacl solution, CuSO
    Cu2+ SO42-
    Electrolysis is the chemical decomposition of a substance brought about by a direct current passing through either a solutions of or a Molten form.

    (2ii)
    Elements that are electolytically reduced are sodium Na, Potassium, Calcium Ca.

    (2b)
    11R and 17S
    (i) Na and Cl ==> Sodium Chloride Nacl
    (ii) Covalent land

    (2bii)
    (i) Bleaching Agents
    (ii) for making important chemicals such as Hcl

    (2iv)
    (i) 11R ==> Sodium has low I.E
    (ii) Fe (iron) react with cold water to form Iron (iii) tetroxide with the release of hydrogen but slow of the iron not hot

    (2ci)
    Cold water on sodium, hydroxide forms at first rate but explode with hot water

    (2cii)
    When water is added to blue anhydrous copper (ii) chloride the colour changes from blue to pink

    (3ai)
    Gay Lussac’s Law of combining volumes states that if gasses react they do so in volume which bears a simple ratios and to the volume of the product. If gaseous provided that the temperature and pressure remains constant

    (3aii)
    V1 = 250cm3
    T1 = 250c
    T2 = ?
    V2 = 2v1
    = 25 + 273
    = 2 x 250cm3
    = 298k
    = 500cm3

    V1/T1 = V2/T2
    250/298 = 500/T2
    250 T2 = 500 x 298
    T2 = 500 x 278/250
    = 596k

    (3bi)
    Atomicity of an element is the total number of atoms present in one molecule of an element or a compound

    (3bii)
    – Monatomic has –> Helium, Neon
    – Triatomic Gas –> Ozone O3

    (3biii)
    – it is used as antiseptic
    – it is in bleaching delicate materials such as Silk, wool, pulp etc

    (3iv)
    – it is a colourless, odourless gas
    – it is neutral to moist litmus paper

    (3di)
    Indicator is a substance that undergo a distinct observable when conditions in its solution change.
    (3dii)
    tabulate
    Indicator : Phentphthalin
    Color in base Medium :purple
    Color in acid medium : colourless
    (3diii)
    Equation of preparation of Hydrogen
    Na(l) + H20(g) —–> NaOH(aq) + H2(g)
    Sodium is reacted with cold water to give hydrogen gas
    Uses:
    (i) It is used in making hydrogen bond
    (ii) it is used in making HCL, HNO

    (4ai)
    – to get the reduction of impurities
    – to avoid other constituents to stick to them

    (4aii)
    CuCO3(s) D–> CuO + CO2
    1mole of CuCO3 produce 1 mole of CO2
    0.081 mole would give 0.081 moles of CO2
    No of mole = mass/molar mass
    = 10/123.5
    = 0.081 moles
    CuCO3 ==> 123.5
    No of mole of CO2 = Volume given/22.4
    0.081 = volume/22.4
    V = 22.4 x 0.081
    = 1.8144dm3

    (4bi)
    TABULATE:
    Endothermic | Exothermic
    UNDER EDOTHERMIC
    (1) heat is absorbed to the surroundings
    (2) The Enthalpy change is posture (+ve)
    UNDER EXOTHERMIC:
    (1) Heat is evolved to the surroundings
    (2) The enthalpy changes here is negative

    (4bii)
    (i) Sodium hydroxide pellets in water is Exothermic
    (ii) Ammonium Chloride in water is Endothermic
    (iii) Con H2SO4 acid is Exothermic

    (4ci)
    TABULATE:
    Saturated Fatty Acids | Unsaturated Fatty Acids
    UNDER SATURATED FATTY ACIDS:
    – Their bonds to accepts any form of constituents are full
    UNSATURATED FATTY ACIDS:
    – they still have more bond space so they are Unsaturated
    (4cii)
    Fatty acid are work acids because they dissociate partially in water and the Hydrogen or Hydroxonium ions are not concentrated
    ==================



    If you like this story, please share it on Facebook, Twitter, Google+, Pinterest ETC.
    also don't forget to leave a Reply, we would very MUCH appreciate Your Comments On This Post Below. Thanks!
    Master Solution November 28, 2018 Categories: NECO 673


    Related Posts In » NECO
    2023 NECO GCE RESULT IS OUT – SEE HOW TO CHECK YOUR RESULT
    NECO Sets deadline for 2023 GCE registration.
    NECO ANNOUNCES THE RELEASE OF 2023 GCE TIMETABLE (SSCE) FOR EXTERNAL CANDIDATES
    Breaking: NECO SSCE result For 2023 session has been officially released
    NECO ANNOUCES THE COMMENCEMENT OF GCE REGISTRATION 2023/2024
    Neco 2023/2024 Animal Husbandry Objective And Theory Questions And Answers – June/July Expo
    Neco 2023/2024 Marketing Objective And Theory Questions And Answers – June/July Expo
    Neco 2023/2024 Fishery Practical Questions And Answers – June/July Expo
    Neco 2023/2024 Animal Husbandry Practical Questions And Answers – June/July Expo
    Neco 2023/2024 Mathematics Objective And Theory Questions And Answers – July/August Expo
    Neco 2023/2024 Geography Objective And Theory Questions And Answers – July/August Expo
    Neco 2023/2024 Literature In English Drama And Poetry Questions And Answers – July/August Expo
    Neco 2023/2024 Physics Objective And Theory Questions And Answers – July/August Expo
    » See More Posts in- NECO
    Be The First To Add A Comment
    Leave a comment
    Click here to cancel reply.

     Disclaimer                
    Comments, Pictures and culled stories posted on this website will be given due credit and is not the fault of Solutionfans.com if they are given original credit from site culled from. If you have a complaint or a story, Please Send To Us Via [email protected]
    Top
    Forum
    Contact
    © 2018 Solutionfans.com
    © 2016 - solutionfans.com Inc