Question 1 :
The carbon atoms in diamond are bonded to each other by:

Question 5 :
What is the smallest part of the crystal that has the three-dimensional pattern of the whole lattice called?

Question 6 :
<div><span>The phenomenon of existence of an element in more than one physical form is called allotropy.</span><br/></div>

Question 7 :
If X is a non-metal. It will not conduct electricity unless it is carbon in the form of :<br/>

Question 8 :
If X is a non-metal, it will not conduct electricity unless it is carbon in the form of __________.

Question 9 :
Which of the following statements is/are incorrect for diamond?<br/>(a) The refractive index of diamond is highest among solids.<br/>(b) Diamond is hard because all the valence electrons of each carbon atom are involved in bond formation.<br/>(c) Diamond is thermodynamically more stable than graphite.<br/>(d) <span>One carat of diamond represents its weight.</span>

Question 10 :
Which of the following is not an allotropic form of carbon?

Question 13 :
Which of the following compounds would be a white, crystalline solid?

Question 15 :
A non-metal $X$ exists in two different forms $Y$ and $Z$. $Y$ is the hardest natural substance whereas $Z$ is a good conductor of electricity. $Y$ is :<br/>

Question 16 :
Which of the following compounds would be a white, crystalline solid?

Question 18 :
Compounds with identical crystal structure and analogous chemical formula are called:

Question 21 :
The allotrope of carbon which is a good conductor of heat and electricity is:

Question 22 :
Crystalline form of carbon having 60 carbon atoms joined together is called :

Question 23 :
An allotropic form of carbon used for cutting and drilling is :

Question 26 :
Some solid crystalline compounds slowly change to the gaseous state when left at room temperature in an open container. Which of the following is true about this phenomenon?

Question 32 :
Assertion: Crystalline solids can cause X-rays to diffract. Reason: Interatomic distance in crystalline solids is of the order of $0.1$ nm.

Question 34 :
The melting point of RbBr is $682^\circ C$, while that of NaF is $988^\circ C$. The principal reason that melting point of $NaF$ is much higher than that of $RbBr$ is that :

Question 35 :
Assertion: Glass belongs to the category of ionic solid. Reason: Glass is supercooled liquid.