Question 1 :
Which of the following is not an allotropic form of carbon?

Question 6 :
Which of the following statements is/are incorrect for diamond?<br/>(a)&#160;The refractive index of diamond is highest among solids.<br/>(b)&#160;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)&#160;One carat of diamond represents its&#160;weight.

Question 7 :
Water which gives lather with soap easily is called as hard water.<br/>

Question 11 :
When 2 hydrogen atoms combine to form $H_2$ molecule, the system ______ .

Question 13 :
Assertion: Diamond and graphite are allotropes of carbon Reason: Some elements can have several different structural forms while in the same physical state. These differing forms are called allotropes.

Question 14 :
Which of the following compound will fall in the same homologous series of formic acid $(H-COOH)$?&#160;

Question 16 :
Soaps do not work with hard water containing calcium and magnesium ions because:

Question 17 :
Select the correct I.U.P.A.C. name for [(C$_6$H$_5$)$_3$P $Cl$ Pd Cl$_2$ Pd $Cl$(C$_6$H$_5$)$_3$P]&#160;

Question 18 :
Which gas is produced when compound $X$ reacts with washing soda?