Chemistry Research

1. http://wiki.answers.com/Q/Why_did_it_take_scientist_80_year_to_discover_francium

Francium is a natural chemical element but the total quantity of francium in the earth crust is only approx. 30 g. Francium has ca. 40 isotopes and isomers but only two are natural: 221Fr (in the neptunium decay chain series) and 223Fr (in the actinium decay chain series). Artificially preparation of francium isotopes is also extremely difficult and expensive; and the chemistry and physics of isotopes was developed essentially after 1940. Supplementary, the most stable isotope of francium has a half life of only 21,8 minutes and is strongly radioactive; the half lives of the artificially prepared isotopes are more smaller.

http://wiki.answers.com/Q/Why_did_it_take_another_80_years_to_discover_francium_after_all_the_other_alkali_metals

Francium is a very unstable element it is estimated that only about 30 grams exist in the earth's crust. Scientists knew that an element like Francium should exist but had yet to find it. It was found in very small amount in uranium ore (only a few atoms) noticed by it's distinct radiation as the most stable isotope has a half-life of on 22 minutes

http://wiki.answers.com/Q/Was_the_discovery_of_Francium_delayed_because_of_a_lack_of_technology_at_the_time_among_other_reasons

Francium was found 80 years after the others because it is very rare on the Earths surface and there is less than an ounce of it in the earths crust. Also the fact that the technology was limited didn't help.

2. http://www.teacherlink.org/content/science/instructional/activities/melting/Melting- print.PDF

3. http://www.chemguide.co.uk/inorganic/group1/reacth2o.htm

This page looks at the reactions of the Group 1 elements - lithium, sodium, potassium, rubidium and caesium - with water. It uses these reactions to explore the trend in reactivity in Group 1.

All of these metals react vigorously or even explosively with cold water. In each case, a solution of the metal hydroxide is produced together with hydrogen gas.

http://home.clara.net/rod.beavon/incat2.htm

All of the metals react in a similar way. Lithium reacts slowly, melting and rushing about the surface of the water. Sodium reacts vigorously, and may catch fire; potassium reacts violently and always inflames. Rubidium and caesium react extremely violently, and would sink but for the fact they don’t survive for long enough.