Respuesta :
Answer:
Period: 1
Group: 18
Explanation:
Helium has a period no. 1 and found in the group 18. Group 18 consists of Noble gases. It has atomic no. 2. It is named after Greek name of Sun i.e. Helios. An interesting fact about Helium is it was discovered on Sun before Earth. It was discovered during the spectral analysis of Eclipsed Sun in 1868 by Capt. C T Haig, Geroges Rayet, Normon Pogson, and Lt. John Herschel. It is odorless, colorless, non toxic, tasteless and inert gas.
It is the second most abundant element in the observable universe, hydrogen being the most abundant.
