UNUNSEPTIUM - RADIOACTIVE HALOGEN

7) The incorrect statement regarding the element Ununseptium is:

a) It belongs to group of halogens. 

b) It belongs to 7th period of periodic table:  

c) It is a radioactive element. 

d) It is a strong metal.

Logic and solution:

Ununseptium, Uus is the temporary IUPAC name of element with atomic number 117. Its existence  is not yet confirmed.

The name itself gives the idea about atomic number. "Un" denotes 1 and "Sept" denotes 7.

Un un sept
1 1 7

Since the atomic number is 86+31=117; it should belong to halogens group. 

How do we arrive at this conclusion? 

You know that 86 is the atomic number of Radon, Rn (see below), a noble gas. Since Rn belongs to 6th period, add 32 to get next element that belongs to 7th period. Hence we can find next noble gas at 86+32 = 118.  Since the atomic numbers of halogens are less by one by those of noble gas elements, we can conclude, ununseptium is a halogen. 

     Group
17 18
P

e

r

i

o

d

1   2He
2 9F 10Ne
3 17Cl 18Ar
4 35Br 36Kr
5 53I 54Xe
6 85At 86Rn
7 117Uus 118Uuo

 

 

Conclusion:

It is a halogen and belongs to 7th period. 

We know that all the elements after Uranium, U with atomic number 92 are radioactive.

Halogens are expected to be strong non metals. Therefore the 4th statement is incorrect. 

Homework:

1) What is the outer electronic configuration of Uus?

2) What might be the physical state of Ununseptium in the elemental state? Solid or liquid or gas?

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Author: Aditya vardhan Vutturi
www.adichemistry.com