19,000+ solved questions for JEE Advanced, JEE Mains, NEET & IChO — with answers and expert explanations.
Percentage of lead in lead pencil is (AIPMT 1999)
Assertion: Silicones are hydrophobic in nature. Reason: Si–O–Si linkages are moisture sensitive. (AIIMS 2006)
Which of the following does not show electrical conduction? (AIPMT 1999)
The colour imparted by Co(II) compounds to glass is (AIIMS 2006)
Carbon and silicon belong to (IV) group. The maximum coordination number of carbon in commonly occurring compounds is 4, whereas that of silicon is 6. This is due to (AIPMT 1994)
Boron compounds behave as Lewis acids, because of their (AIPMT 1996)
In graphite, electrons are
Which glass will not crack when temperature changes ? (DUMET 2006)
A type of zeolite used to convert alcohols directly into gasoline is
Which of the following types of forces bind together the carbon atoms in diamond? (AIPMT 1992)
In which of the following the inert pair effect is most prominent ?
Litharge is chemically (AIIMS 2007)
The reaction which is not involved in thermite process: (a) 3Mn O 8Al 9Mn 4Al O + ¾¾® + (b) Cr O 2Al 2Cr Al O + ¾¾® + (c) 2Fe Al O Fe O 2Al + ¾¾® + (d) B O 2Al 2B Al O + ¾¾® +
Anodised aluminium is :
What is the number of free electrons present on each carbon atom in graphite ?
The purest form of coal is
In graphite, the layers of carbon atoms are held by
Identify the incorrect statement.
Identify X in the reaction : (steam) X 2H O XO 2H D + ¾¾® +
Which of the following is not from 14 th group
Identify the wrong example from the following for the group 14 elements.
Which of the following is not true about structure of diamond and graphite ?
Alumina may be converted into anhydrous aluminium chloride by:
Moderate electrical conductivity is shown by
The incorrect statement regarding above reactions is: