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. 

17 18






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




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. 


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