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Learn about the properties, manufacturing, and characteristics of alkali and alkaline earth metals. Discover how these reactive metals interact with water, their storage methods, and their uses. Gain valuable insights into the periodic table and the "s" block elements.
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Part I “s” block, Groups 1 & 2 Active Metals
Alkali Metals • Group 1 elements • 1 valence electron (half filled S – sublevel) • most reactive metals. • are not found uncombined in nature (elemental) • are found as salts that are very soluble in water • react with water to make Hydrogen gas and a solution of the alkali metal hydroxide. (strong bases) • 2Na(s) + 2H2O(l) 2NaOH(aq) + H2(g) • alkaline solutionsare “basic” solutions pH 7.1-14.0
Storage of Alkali Metals • react with water so rapidly and exothermically (gives off lots of energy) that the Hydrogen often burns as it is produced. • are usually stored under oil or kerosene to keep them from reacting with the oxygen or water in the air.
Alkali Metal Manufacturing • Sodium is the only one manufactured on a large scale. • To produce the free metal, sodium ions must be forced to gain electrons (reduction). • The electrolysis (add electricity to break down) of molten sodium chloride makes elemental sodium. • Also produced is Chlorine gas - another useful chemical
General Characteristics of Alkali Metals • low density • high conductivity • low melting points • soft consistency • shiny when freshly cut
Alkaline Earth Metals • Group 2 elements • They have 2 valence electrons (completed S – sublevel) • Group 2 are less reactive than Group 1. (but still found only as compounds in nature) • do not need to be stored in oil • react with water to produce basic, (alkaline) solutions. (pH 7.1 – 14.0) • Solid Calcium reacts with water to produce H2(g) slowly • salts are less soluble than salts from group 1. • Sea water has an abundant amount of magnesium and calcium ions. (2 most commercially useful from Group 2)
Alkali Earth Metal Manufacturing • Lime– is Calcium Oxide (CaO) • Slaked Lime – is Calcium Hydroxide (Ca(OH)2) • Both are in important to industry
Part II “p” blockGroups 13 - 18 Metals and Nonmetals
Aluminum and Group 13 • Boron is a metalloid (Semiconductor), common in minerals • Used to make glass and water softeners • Aluminium is so useful it was once as expensive as silver • Most common metal in Earth’s crust. • Gallium is not often used in thermometers instead of mercury. • Indium and Thallium are rare.
