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Main-Group Metals. The Activity of Metals. Lithium, sodium, and potassium all react with water. The rate of this reaction increases as we go down this column.
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The Activity of Metals Lithium, sodium, and potassium all react with water The rate of this reaction increases as we go down this column
Class I Metals: The Active MetalsLi, Na, K, Rb, Cs (Group IA)Ca, Sr, Ba (Group IIA)Class II Metals: The Less Active MetalsMg, Al, Zn, MnClass III Metals: The Structural MetalsCr, Fe, Sn, Pb, CuClass IV Metals: The Coinage MetalsAg, Au, Pt, Hg
The most active metals are so reactive that they readily combine with the O2 and H2O vapor in the atmosphere and are therefore stored under an inert liquid, such as mineral oil.
Important trends down the group with increase in atomic number:1. The atoms get bigger (as more electron shells are added).2. The element gets more reactive.3. Down the group the reaction gets faster and more violent.4. Generally the hardness decreases (can be cut with a knife).5. The melting point and boiling point generally decrease.6. Generally the density increases. (due to increase in atomic mass)7. Rubidium and cesium are very explosive with water.8. Ionization energy decreases.
Reactions Halogens; 2 Na(s) + Cl2(g)→2 NaCl(s) Hydrogen: 2K(s) + H2 (g) → 2 KH(s) Nitogen: 3Li + → Li3N Oxygen: 4 Li(s) + O2 (g) → 2 Li2O(s)oxide 2 Na(s) + O2 (g) → Na2O2(s) peroxides K(s) + O2 (g) → KO2(s) superoxides Water: 2Na(s) + 2H2O (l) → 2 Na+ + 2 OH- + H2
Group IIA: The Alkaline-Earth Metals M → M2+ →+ 2e-
Halogens; Mg (s) + Cl2(g)→MgCl2(s) Hydrogen: Ca(s) + H2 (g) → CaH2(s) Nitogen: 3 Mg(s) + N2(g) → Mg3N2(s) Oxygen: 2 Mg(s) + O2(g) → 2 MgO(s) oxide Ba(s) + O2(g) → BaO2(s) peroxides Ca,Sr, Ba Water: Ca(s) + 2 H2O (l) →Ca2+(aq) + 2 OH-(aq) + H2(g) Ca,Sr, Ba Steam Mg(s) + H2O (g) → MgO(s) + H2(g) Reactions
Reactions 2 Al(s) + 3 Br2(l)→ Al2Br6(s) 4 Al(s) + 3 O2(g) → 2 Al2O3(s) 16 Al(s) + 3 S8(s) → 8 Al2S3(s) Aluminum reacts with concentrated acids 2 Al(s) + 6 H+(aq) → 2 Al3+(aq) + 3 H2(g) Aluminum reacts with concentrated bases 2 Al(s) + 2 OH-(aq) + 6 H2O(l) → 2 Al(OH)4-(aq) + 3 H2(g)
Group IVA: Tin and Lead Dr.Riham Hazzaa
Lead reacts with air to form a thin coating of PbO and/or PbCO32 Pb(s) + O2 (g) → 2 PbO(s)PbO(s) + CO2 (g) → PbCO3(s) Tin does not react with either air or water at room temperature Reacts with hot air Sn(s) + O2(g) → SnO2(s) Reacts with steam Sn(s) + 2 H2O(g) → SnO2(s) + 2 H2(g) Dr.Riham Hazzaa
Tin, when heated, reacts with either concentrated hydrochloric acid or concentrated sulfuric acid.Sn(s) + 2 H+(aq)→ Sn2+(aq) + H2(g)Lead reacts slowly with hydrochloric acid at room temperature and with concentrated sulfuric acid at temperatures above 200C.Pb(s) + 2 H+(aq) → Pb2+(aq) + H2(g) Dr.Riham Hazzaa