1. Elements; Argon, Rhodium, & Protactinium.
By: Morgan Brandi(:

2. Argon 1. Atomic number – 18 (Electrons -18, Neutrons – 22)
2. Atomic weight –
3. Element classification – nonmetal
4. Period group – 3
5. Group name – noble gas
6. Number of stable isotopes – 3. (Calcium)
7. Argon was discovered by Sir William Ramsay, a Scottish chemist and Lord Rayleigh an English chemist in 1894.
8. Argon makes up .93% of the earth’s atmosphere, making it the 3rd most abundant gas.
9. Element configuration – 1s2, 2s2, 2p6, 3s2, 3p6.
(36x x x = )

3. Rhodium 1. Atomic number – 45 (Electrons 45, Neutrons -58)
2. Atomic weight –
3. Element classification – metal
4. Group name – none
5. Number of stable isotopes – 1
Rhodium
6. Electron configuration – 1s2, 2s2, 2p6, 3s2, 3p6, 3d10, 4s2, 4p6, 4d8, 5s1.
7. Rhodium was discovered by William Hyde Wollaston, an English chemist, in 1803 shortly after shortly after his discovery of the element palladium. Rhodium is used to make electrical contacts, as jewelry, but is mostly used as an alloying agent in other materials.

4. Protactinium 1. Atomic number – 91 (Electrons – 91, neutrons – 140)
2. Atomic weight –
3. Element classification – metal
4. Group name – actinide
5. RADIOACTIVE
6. Period number- 7
1. Number of stable isotopes – 0
2. Protactinium was first identified by Kasimir Fajans and O.H. Gohring in 1913 while studying uranium’s decay chain. Protactinium is a rare, poisonous and expensive element that is present in uranium ores in very small amounts.
3. Electron configuration – 1s2, 2s2, 2p6, 3s2, 3p6, 3d10, 4s2, 4p6, 4d10, 4f14, 5s2, 5p6, 5d10, 5f2, 6s2, 6p6, 6d1, 7s2.

8. Works Cited.
….. The End!