Question 1 :
Name two product of the given reaction.<div><span>$Zn + \underset{(Steam)}{H_2O} \rightarrow $</span><br/></div>

Question 5 :
If copper is kept open in air, it slowly loses its shining brown surface and gains a green coating. It is due to the formation of

Question 6 :
Which of the following will replace hydrogen from acids to form salts?<br/>$Cu, Hg, Na, Ag$

Question 7 :
Name one metal that will not react with cold water but will react with steam.

Question 8 :
1 kg of iron occupies less space compared to 1 kg of sponge. Why?

Question 10 :
Elements and compounds that occur naturally in the earth's crust are called:

Question 11 :
The gas given off when a metal reacts with an acid is

Question 13 :
Which of the following is not a property of an alkali?

Question 15 :
Which of the following statements about Mendeleev's Periodic Table is incorrect?

Question 17 :
In the first two groups of periodic table, the group number represents the :<br/>

Question 18 :
The group in which all the elements do not have same number electrons in their valence shell is :

Question 19 :
Which periods were not divided into two series in the Mendeleev's periodic table?

Question 20 :
For which of the pair Newland octave rule is not applicable?

Question 21 :
Which of the following can be classified as Dobereiner's triads?<div>(a) P, As, Sb <div>(b) Cu, Ag, Au</div><div><span>(c) S, Se, Te<br/></span></div></div>

Question 22 :
Doberiener's system of classification into triads was not found to be useful as he could identify only:

Question 24 :
Which group of elements could be placed in Mendeleev's Periodic Table without disturbing the original order?<br/>

Question 27 :
Which of the following accounts best for the fact that fluorine atom is smaller than that of oxygen?

Question 28 :
<SPAN>Based on general trends in the periodic table, predict which element in each of the following pairs has the most metallic character.<BR>(i) Sn or Pb&nbsp;&nbsp; &nbsp;(ii) Ag or Sr&nbsp;&nbsp; &nbsp;(iii) Al or B&nbsp;&nbsp; &nbsp;(iv) Br or As</SPAN>

Question 29 :
Which of the following properties generally shows a decreasing trend along a period?

Question 32 :
Which of the following is not an allotropic form of carbon?

Question 36 :
Following are the uses of a substance.<div><br/><span>(i) It is used as an abrasive for cutting glass.</span><div><br/>(ii) It is used as a tip of deep boring drills.</div><div><br/>(iii) It is used for making dies for drawing wires.</div><div><br/>(iv) It is used in generating laser beams in electronics.</div><div><br/><div>What is the name of this substance?</div></div></div>

Question 38 :
LPG is liquefied petroleum gas which is a compound of butane and propane and used as :

Question 39 :
Oils on treating with hydrogen in the presence of palladium or nickel catalyst form fats. This is an example of_________.<br/>

Question 40 :
Assertion: When a hydrocarbon is combusted in air, carbon monoxide is always the major product.<br/>Reason: Air contains much more nitrogen than oxygen.