Chemistry
Explain with the help of :
(i) an ionic equation
(ii) electron dot structural diagram
the formation of the following :
(a) Sodium chloride
(b) Calcium oxide
(c) Magnesium chloride.
(at. nos. Na = 11, Cl = 17, Ca = 20, O = 8, Mg = 12)
Answer
(a) Sodium Chloride :
Ionic equation
Na - 1e- ⟶ Na1+ [oxidation]
[atom] [cation]
[2,8,1] [2,8]
Cl + 1e- ⟶ Cl1- [reduction]
[atom] [anion]
[2,8,7] [2,8,8]
Na + Cl ⟶ Na1+ Cl1- ⟶ NaCl
Electron dot structural diagram
(b) Calcium Oxide
Ionic Equation
Ca - 2e- ⟶ Ca2+ [oxidation]
[atom] [cation]
[2,8,8,2] [2,8,8]
O + 2e- ⟶ O2- [reduction]
[atom] [anion]
[2,6] [2,8]
Ca + O ⟶ Ca2+O2- ⟶ CaO
Electron dot structural diagram
(c) Magnesium chloride.
Ionic Equation
Mg - 2e- ⟶ Mg2+ [oxidation]
[atom] [cation]
[2,8,2] [2,8]
2Cl + 2e- ⟶ 2Cl- [reduction]
[atom] [anion]
[2,8,7] [2,8,8]
Mg + 2Cl ⟶ Mg2+2Cl- ⟶ MgCl2
Electron dot structural diagram
Related Questions
State which of the following are oxidation reactions and which are reduction reactions.
(a) (i) Cu ⟶ Cu2+ + 2e-
(ii) Cu2+ + 2e- ⟶ Cu
(iii) Sn4+ + 2e- ⟶ Sn2+
(iv) 2Cl- ⟶ Cl2 + 2e-
(v) Fe2+ ⟶ Fe3+ + 1e-
(vi) X + 2e- ⟶ X2-
(vii) Y - 1e- ⟶ Y1+
(viii) Z3+ + 1e- ⟶ Z2+
(b) (i) Zn ⟶ Zn2+
(ii) S ⟶ S2-
(iii) Sn2+ ⟶ Sn
(iv) Fe2+ ⟶ Fe3+
Fill in the blanks with appropriate word/s from the brackets :
NaCl an electrovalent compound is formed as a result of transfer of …………… (one, two, three) valence electrons from metallic sodium to non-metallic chlorine atom. CaO is similarly formed as a result of transfer of …………… (one, two, three) valence electron/s from metallic calcium to non-metallic oxygen and magnesium chloride by transfer of …………… (one, two, three) valence electron/s from …………… (one, two) magnesium atom/s to …………… (one, two) chlorine atom/s.
Fill in the blanks with appropriate word/s from the brackets :
Covalent compounds are formed by sharing electron pairs between non-metallic atoms. Non-metallic atoms having …………… , …………… , …………… valence electrons (4, 5, 6, 7) share one, two or three pairs of electrons respectively.
Explain the terms 'oxidation' and reduction' with reference to an atom or ion.