00:02
Dear students, we have to see the description given in the first column and if any element matches with this description we have to write here yes otherwise no.
00:12
And if yes, then you have to write the name of the element here, symbol of the element here.
00:18
So first description is an element in period 1 and group 5a.
00:23
In period 1 we have 2 elements, hydrogen and helium.
00:28
1 belongs to group 1 and 1 belongs to group 0 or 18.
00:33
Therefore it does not have no element matches with the description then the answer here is no.
00:45
Then the second one is a semi -metal in group 8a.
00:49
Now the second description is a semi -metal in group 8a.
00:54
Group 8a, nothing but our noble gases.
01:03
In it we have the elements helium, neon, argon, krypton, genon and radon.
01:12
And out of this, radon is a semi -metal.
01:15
So an element less than 92 match the description, yes, that is radon.
01:25
Then coming to the next one a noble gas with a lower atomic number, then gallium...