Question 1 :
A solid which is not transparent to visible light and whose conductivity increases with temperature is formed by :<br>

Question 2 :
The maximum covalency exhibited by an element is 6. The number of unpaired electrons in the ground state of an atom is:

Question 3 :
Assertion: $LiF$ has more covalent character than $CsF$. Reason: Lattice energy of $CsF$ is less than that of $LiF$.

Question 5 :
Assertion: In the formation of water molecule, both hydrogen and oxygen atoms attain octet of electrons. Reason: Oxygen atom forms two ionic or electrovalent bonds with two hydrogen atoms.

Question 6 :
Some of the following properties are important in determining whether an element has metallic properties<br>I : atomic number<br>II : atomic weight<br>III : number of valence electrons<br>IV : number of vacant atomic orbitals<br>V : total number of electronic shells in the atom<br>Select correct properties from the codes given below

Question 10 :
During the formation of $NaCl$, transfer of electron is from $X$ orbital of $Na$ to the $Y$ orbital of $Cl$. Then $X$ and $Y$ are respectively: