CBSE · Class 10 · Chemistry · Chapter 3

Metals and Non-Metals — Formula Sheet

Board Formulas

9 formulas

1.Ionic Bond Formation★
$N a ⟶ N a^{+} + e^{-}; C l + e^{-} ⟶ C l^{-}$
Metal loses electron(s) to attain noble-gas configuration; non-metal gains. Attraction between the two ions is the ionic bond.
2.Metal + Oxygen
$2 M + O_{2} ⟶ 2 M O$
Metal oxides are usually BASIC. Some (Al₂O₃, ZnO, PbO) are amphoteric. Example: 4Al + 3O₂ → 2Al₂O₃.
3.Metal + Water
$2 N a + 2 H_{2} O ⟶ 2 N a O H + H_{2} (g)$
Reactivity decreases K > Na > Ca > Mg > Al > Zn > Fe. Mg reacts with hot water, Zn/Fe only with steam. Cu does not react.
4.Metal + Dilute Acid★
$M + 2 H C l ⟶ M C l_{2} + H_{2} (g)$
Metals ABOVE hydrogen in reactivity series liberate H₂ with dilute HCl / H₂SO₄. Cu, Ag, Au do not.
5.Displacement in Salt Solution
$F e + C u S O_{4} ⟶ F e S O_{4} + C u$
More reactive metal displaces less reactive one from its salt solution. Basis of many extraction methods.
6.Amphoteric Oxide
$A l_{2} O_{3} + 6 H C l ⟶ 2 A l C l_{3} + 3 H_{2} O$
Same oxide also reacts with a base: Al₂O₃ + 2NaOH → 2NaAlO₂ + H₂O. Hence AMPHOTERIC.
7.Reduction of Metal Oxide (Smelting)★
$Z n O + C ⟶ Z n + C O$
Reduction of moderately reactive metal oxide using carbon (coke). Example: Fe₂O₃ + 3C → 2Fe + 3CO.
8.Thermite Reaction
$F e_{2} O_{3} + 2 A l ⟶ 2 F e + A l_{2} O_{3}$
Highly exothermic; molten iron produced. Used to weld railway tracks and cracked machine parts.
9.Electrolytic Refining
$Impure M (anode) ⟶ M^{n +} (a q) + n e^{-}; M^{n +} + n e^{-} ⟶ M (cathode)$
Pure metal deposits on the cathode; impurities settle as ANODE MUD. Used to purify Cu, Zn, Ag.