Answer:
Only to elements are gases at room temperature and standard pressure.
Fluorine and chlorine.
Explanation:
The group 17 is called halogen.
There are five elements in halogen group.
All halogens required one electrons to complete the octet and to get the noble gas electronic configuration.
All halogen elements have seven valance electrons.
Halogen elements:
Fluorine, chlorine, Bromine, iodine and astatine
Fluorine is gas at room temperature which s 25°C and standard pressure which is 1 atm.
It is present in the from of F₂.
Chlorine is also gas at room temperature and standard pressure.
It is present in the from of Cl₂.
The bromine is liquid under these condition.
Iodine and astatine are solids.
As we move down the group their melting and boiling points increases.
The half life for radioactive can be calculated as:
N /N0 = (1 /2) ^ n
n = T /T half
According to question there are n number of half life are present which would result in remaining amount of element as n.
Answer:the energy required by an atom to lose or gain electron (e-) to be able to form ions.either cation or anion.
Explanation:
to lose or gain e- an atom has to donate or receive e- to to this it requires the more easily it can lose an electron the more electro positive it is and the more easily it gains electron the more electro negative it is.
