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(a) Consider the following atoms: \(^R_T\)X; \(^S_T\)X. (i) State the phenomenon ...

(a) Consider the following atoms: \(^R_T\)X; \(^S_T\)X.
(i) State the phenomenon exhibited by the two atoms.
(ii) What is the difference between the atoms?
(iii) Give two examples of elements that exhibit the phenomenon stated in (ai)
(iv) lf T is 17, write the electron configuration of the element

(b)(i) State two differences between metals and-non-metals with respect to their:
I. physical properties;
2. chemical properties.
(ii) Give one example of each for the following compounds:
I. an amphoteric oxide;
II. a hydride which evolves hydrogen when reacted with water;
Ill. a trioxocarbonate (IV) salt which is readily decomposed on heating;
IV. a chloride salt which is readily hydrolyzed in water.

(c)(i) State three characteristic properties of transition metals.
(ii) Write the electron configuration of \(_{30}Zn\)
(iii.) Explain briefly why zinc is not considered as a typical transition element.

(d) Consider the reaction represented by the following equation:- Na\(_2\)CO\(_{3(aq)}\) + MgCl\(_{2(aq)}\) ----> 2NaCl\(_{(aq)}\) + MgCO\(_{3(aq)}\). Calculate the mass of sodium trioxocarbonate (IV) needed to produce 3.36 of magnesium trioxocarbonate (IV). [C = 12.0, O = 16.0, Na = 23.0, Mg = 24:0 ]
Take Free Practice Test On 2026 JAMB UTME, Post UTME, WAEC SSCE, GCE, NECO SSCE
    Correct Answer: Option n
    Explanation:
    (a)(i) Isotopy
    (ii) They have different mass numbers or number of neutrons.
    (iii) —Hydrogen, —Chlorine. —Carbon, —Oxygen.
    (iv) 1 S\(^2\)2S\(^2\)2P\(^62\)3S\(^2\)3P\(^5\)

    (b)(i) 1. DIFFERENCES IN PHYSICAL PROPERTIES
    METALS NON — METALS
    Good conductors of heat and electricity Poor conductors of heat and electricity
    Malleable - can be beaten into thin sheets Not malleable / brittle
    Ductile — can be stretched into wire Non ductile / biittle
    Possess metallic luster Do not possess metallic luster
    Are sonorous Not sonorous
    Solid at room temperature except mercury / high melting point Solids, liquids or gases at room temperature / low melting point




    2. DIFFERENCES IN CHEMICAL PROPERTIES
    METALS NON METALS
    Lose their valence electrons easily / ionize by electron loss Gain or share valence electrons easily / ionize by electron gain
    Form oxides that are basic / amphoteric Form oxides that are acidic / neutral
    Are good reducing agents Are good oxidizing agents
    Have lower electro negativities Have higher electro negativities
    Have low ionization energy Have high ionization energy
    (Some reactive metals) react with dilute acids to give off hydrogen Do not react with dilute acids to give off hydrogen.




    (ii) (l) BeO, Al\(_2\)O\(_3\), ZnO, SnO\(_2\), PbO, PbO\(_2\)
    (II) LiH, NaH, KH, CaCO\(_3\) MgH\(_2\)
    (III) Li\(_2\)CO\(_3\), BeCO\(_3\), MgCO\(_3\), CaCO\(_3\), ZnCO\(_3\), PbCO\(_3\)
    (IV) AlCl\(_3\), MgCl\(_2\), PCl\(_3\), SiCl\(_4\), NH\(_4\)Cl

    (c)(i) - form coloured compounds / ions, - exhibit variable oxidation states. - form complex compounds / ion. - have magnetic properties (paramagnetism). - have catalytic properties.
    (ii) —> 1s\(^2\)2s\(^2\)2p\(^6\)3s\(^2\)3p\(^6\)3d\(^{10}\)4s\(^2\) are fully filled

    (d) Mr(MgCO\(_3\)) = 24 + 12 + (16 x 3) 84
    Mr(Na\(_2\)CO\(_3\)) = (23 x 2) +12 + (3 x 16) = 106
    moles of MgCO\(_3\) = \(\frac{3.36}{84}\) = 0.04
    moles of Na\(_2\)CO\(_3\) = moles of MgCO\(_3\) = 0.04
    mass of NaCO\(_3\) = 0.04 x106 = 4.24g
    OR
    Mr(MgCO\(_3\)) = 24 + 12 + (1 6 x 3) 84
    Mr(Na\(_2\)CO\(_3\)) = (23 x 2) +12 + (3 x 16) = 106
    84g of MgCO\(_3\) produced from 10\(^6\)g Na\(_2\)CO\(_3\)
    3.36g of MgCO\(_3\) will be produced
    From 106 x \(\frac{3.36}{84}\) = 4.24g

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