S Elements

1. S Elements Groups 1 and 2

2. Properties of Group 1A • These are (except for hydrogen) soft, shiny, low-melting, highly reactive metals, which tarnish when exposed to air. • The valence electron is easily lost, forming an ion with a 1+ charge. • larger atomic radii and low ionization energies • They tend to donate their electrons in reactions

3. Group 1- Alkaline Metals • Hydrogen • Lithium • Sodium • Potassium • Rubidium • Cesium • Francium

4. Hydrogen- H • 1 proton • 1 electron • 0 neutron • 1s1- electron configuration • A colorless, highly flammable gaseous element, the lightest of all gases and the most abundant element in the universe. • Uses- The most common uses of Hydrogen are in Hydrogen Peroxide, H Bomb, Fuel Cells, Fuel, Hydrogen Generators, Hydrogen Powered Cars.

5. Lithium -Li • 3 protons • 3 electrons • 4 neutrons • 1s2 2s1 • A soft, silvery, highly reactive metallic element that is used as a heat transfer medium, in thermo-nuclear weapons, and in various alloys, ceramics, and optical forms of glass. • Lithium was discovered by Johann Arfvedson in 1817

6. Sodium - Na • 11 protons • 11 electrons • 12 neutrons • 1s2 2s2 2p6 3s1 • A soft, light, extremely malleable silver-white metallic element that reacts explosively with water • Sodium, referred to as soda by the English, was isolated in 1807 by Sir Humphrey Davy

7. Potassium- K • 19 protons • 19 electrons • 20 neutrons • 1s2 2s2 2p6 3s2 3p6 4s1 • A soft, silver-white, highly or explosively reactive metallic element that occurs in nature only in compounds. • Potassium was discovered by Sir Humphrey Davy in 1807. • Glass, Soap, Substitute for table salt, Medical, Fertilizers, and Gunpowder

8. Rubidium- Rb • 37 protons • 37 electrons • 48 neutrons • 1s2 2s2 2p6 3s2 3p6 4s2 3d10 4p6 5s1 • A soft silvery-white metallic element of the alkali group that ignites spontaneously in air and reacts violently with water, used in photocells and in the manufacture of vacuum tubes, and fireworks • Rubidium was discovered by Robert Bunsen and Gustav Kirchhoff in 1861

9. Cesium- Cs • 55 protons • 55 electrons • 78 neutrons • 1s2 2s2 2p6 3s2 3p6 4s2 3d10 4p6 5s2 4d10 5p6 6s1 • A soft, silvery-white ductile metal and liquid at room temperature, and used in Atomic Clocks • Cesium was discovered by FustovKirchoff and Robert Bunsen in 1860

10. Francium- Fr • 87 protons • 87 electrons • 136 neutrons • 1s2 2s2 2p6 3s2 3p6 4s2 3d10 4p6 5s2 4d10 5p6 6s2 5d10 6p6 7s1 • An extremely unstable radioactive element of the alkali metals • soft, malleable, ductile, and are good conductors of heat and electricity. • discovered by Marguerite Derey of the Curie Institute in Paris in 1939. • No known use

11. Properties of Alkaline Earth Metals • *The Group 2 elements are all metals with a shiny, silvery-white colour. *harder and denser than sodium and potassium *higher melting points than sodium and potassium *Atomic and ionic radii increase as you move down the Group *Three of these elements give characteristic colors when heated in a flame: Mg brilliant white Ca brick-red Sr crimson Ba apple green

12. Group 2A- Alkaline earth Metals • Beryllium • Magnesium • Calcium • Strontium • Barium • Radium

13. Beryllium- Be • 4 protons • 4 electrons • 5 neutrons • 1s2 2s2 • high-melting, lightweight, corrosion-resistant, rigid, steel-gray metallic element used as an aerospace structural material, as a moderator and reflector in nuclear reactors, and in a copper alloy used for springs, electrical contacts, fluorescent tubes, and non-sparking tools. • Beryllium was discovered in France by Nicolas-Louis Vauquelin in beryl and in emeralds in 1798

14. Magnesium- Mg • 12 protons • 12 electrons • 12 neutrons • 1s2 2s2 • A light, silvery-white, moderately hard metallic element that in ribbon or powder form burns with a brilliant white flame. It is used in structural alloys, pyrotechnics, flash photography, and incendiary bombs. • Magnesium was discovered by Joseph Black, in England, in 1755.

15. Calcium- Ca • 20 protons • 20 electrons • 20 neutrons • 1s2 2s2 2p6 3s2 3p6 4s2 • A silvery, moderately hard metallic element that constitutes approximately 3.5% of the earth's crust and is a basic component of most animals and plants. The most common uses of Calcium are in Dairy products. • Calcium was discovered by Sir Humphrey Davy in 1808 • Fifth most abundant element in the earth's crust

16. Strontium- Sr • 38 protons • 38 electrons • 40 neutrons • 1s2 2s2 2p6 3s2 3p6 4s2 3d10 4p6 5s2 • A soft, silvery, easily oxidized metallic element that ignites spontaneously in air when finely divided. Strontium is used in pyrotechnic compounds and various alloys. • The mineral strontianite was recognised by Adair Crawford in 1790

17. Barium- Ba • 56 protons • 56 electrons • 81 neutrons • 1s2 2s2 2p6 3s2 3p6 4s2 3d10 4p6 5s2 4d10 5p6 6s2 • A soft, silvery-white alkaline-earth metal, used to deoxidize copper and in various alloys. • Barium was discovered by in 1774 by Carl Scheele and extracted by Sir Humphrey Davy in 1808 • Sparkplugs, Vacuum tubes, Fireworks, Fluorescent lamps,Paint, Rat poison

18. Radium- Ra • 88 protons • 88 electrons • 138 neutrons • 1s2 2s2 2p6 3s2 3p6 4s2 3d10 4p6 5s2 4d10 5p6 6s2 5d10 6p6 7s2 • A rare, brilliant white, luminescent, highly radioactive metallic element found in very small amounts in uranium ores and used in Luminescent paints • Radium was discovered by Marie Curie and her husband Pierre Curie in 1898