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.
This is sufficient reason to explain why francium was later discovered and why even today is only slightly studied.
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. This is sufficient reason to explain why francium was later discovered and why even today is only slightly studied.
Eighty Years' War happened in 1568.
Eight is the only single digit number to be spelled with all of its letters in alphabetical order. Eighty is another such number, but it is two digits. I'm not sure if there are others.
The Eighty Year War, also known as The Dutch Revolt (1568-1648) has an estimated death toll of 1,000,000.Please see related links below!
Eighty-four - having been born in April 1926.
The total amount of the francium in the Earth crust is approx. 30 grams.
It is highly unstable. The MOST stable isotope of this stuff has a half life of 22 minutes.
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. This is sufficient reason to explain why francium was later discovered and why even today is only slightly studied.
I'm doing homework on francium for my school the question is... The last element to be discovered had to wait until something else was discovered. What was this? So there had to be something else discovered before it was discovered but i don't know what that other something is help... my homeworkd due in tomorrow.
eighty-eight constellation
Old Octogenarian
"Eighty is".
Eighty-four Or 80 (plus sign) 4
The number 81 is eighty-one.Eighty one.
Eighty dollars.
I spell it as eighty-one.