Question 9 :
Which of the following compounds would be a white, crystalline solid?

Question 10 :
Compounds with identical crystal structure and analogous chemical formula are called:

Question 12 :
Solid $X$ is a very hard solid which is electrical insulator in solid as well as in molten state and has extremely high melting point. What type of solid is it?

Question 13 :
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 15 :
Which type of bonding is responsible for the ability of some solid materials to conduct electricity?

Question 21 :
Assertion: Crystalline solids can cause X-rays to diffract. Reason: Interatomic distance in crystalline solids is of the order of $0.1$ nm.

Question 24 :
<b>Statement-I: &#160;</b>Initially the term pseudo solid was given for solids&#160;which were easily distorted by bending and&#160;compressing forces. They even tend to flow slowly&#160;under its own weight and lose shape.<br/><b>Statement-II:</b> &#160;These characteristics are shown by pseudo solids as in pitch, glass and thus, the name pseudo solid was replaced by supercooled liquids.<br/>

Question 25 :
In a cubic structure of compounds which is made from $X$ and $Y$, where $X$ atoms are at the corners of the cube and $Y$ at the face centres of the cube. The molecular formula of the compound is