Question 3 :
The formula of the most abundant salt of sodium&#160;in nature is:<br/>

Question 6 :
Process in which the extraction of metals from ores is called:<br/>

Question 10 :
In the extraction of iron, the most preferred ores are :

Question 15 :
The extraction of metals from their ores and then refining them for use is known as................. .

Question 25 :
Various processes involved on the extraction of metals from their ores and refining are known as:

Question 29 :
The process of extraction of metal from its ores, is known as :<br/>

Question 30 :
In the extraction of some metals from their ores, coke can be used as:<br/>

Question 38 :
Assertion: Gold occurs in native state. Reason: Gold dissolves in aqua-regia.<br/>Choose the correct option:

Question 39 :
A mineral from which a metal can be extracted on the commercial scale economically is called

Question 41 :
Followed by oxygen which element is the most&#160;abundant in human body?

Question 44 :
Commercially important ore of lead from which it is extracted is

Question 45 :
Aluminium is not present in which of the following minerals ?

Question 46 :
The metal which always exists in free or native state is

Question 49 :
A tin chloride $Q$ undergoes the following reaction (not balanced)<br>$Q + Cl^{-} \rightarrow X$<br>$Q + Me_{3}N \rightarrow Y$<br>$Q + CuCl_{2}\rightarrow Z + CuCl$<br>$X$ is monoanion having pyramidal geometry. Both $Y$ and $Z$ are neutral compounds. Choose the correctoptions(s)<br>

Question 51 :
In metallurgy, the concentration of ore is followed by the dressing of ore.<br>

Question 55 :
The impurities associated with minerals used in metallurgy are collectively called

Question 57 :
Which of the following is an example of a halide ore?

Question 59 :
Which one of the following is the chief ore of copper?

Question 60 :
Which among the following is not a mineral of iron ?&#160;<br/>

Question 62 :
Which one of the following element is present in the eyes of certain animals ?

Question 65 :
Borax is used as cleansing agent because on&#160;dissolving in water it gives ________________.

Question 66 :
A solution is a homogeneous mixture of two or more substances. Which of the following is a solution?

Question 68 :
A number of elements available in earth's crust but most abundant elements are:

Question 72 :
Match the columns.<table class="wysiwyg-table"><tbody><tr><td>List I</td><td>List II</td></tr><tr><td>A. Bauxite</td><td>$1.$ Lead</td></tr><tr><td>B. Haematite</td><td>$2.$ Thorium</td></tr><tr><td>C. Galena</td><td>$3.$ Aluminium</td></tr><tr><td>D. Monazite</td><td>$4.$ Iron</td></tr></tbody></table>

Question 74 :
The correct set of carbonate ore is:<br/>(a) &#160;Magnesite<br/>(b) &#160;Siderite<br/>(c) &#160;Zincite<br/>(d) &#160;Argentite<br/>

Question 75 :
CO is toxic because it forms complex with _________ in the blood.

Question 76 :
Assertion: All minerals are ores. Reason: Ores are minerals from which metal can be extracted conveniently and econoically.

Question 77 :
In chromite ore, the oxidation number of iron, and chromium are respectively.

Question 79 :
Those natural occurring components from which element can be extracted profitably and conveniently known as

Question 81 :
One of the natural minerals of sodium is tincal. Its formula is:

Question 83 :
Which of the following is not correctly matched with respect to the processes involved in the extractive metallurgy of the respective metal?<br>

Question 89 :
Match the following:<br/><table class="wysiwyg-table"><tbody><tr><td>Column I</td><td>Column II</td></tr><tr><td>A. Sphalerits&#160;</td><td>p. $FeCO_3$</td></tr><tr><td><b></b>B. Malachite</td><td>q. $ZnCO_3$</td></tr><tr><td>C. Calamine&#160;</td><td>r. $Na_3AlF_8$</td></tr><tr><td>D. Cryolite</td><td>s. $CuCO_3\cdot Cu(OH)_2$</td></tr><tr><td>E. Siderite&#160;</td><td>t. $ZnS$</td></tr></tbody></table>

Question 91 :
Match column A with column B and select the correct option:<br/><table class="wysiwyg-table"><tbody><tr><td><br/></td><td>Column A<br/>(Ore)</td><td></td><td>Column B<br/>(Nature of ore)</td></tr><tr><td>(a)</td><td>Copper glance</td><td>(i)</td><td>Sulphate ore</td></tr><tr><td>(b)</td><td>Calamine</td><td>(ii)</td><td>Halide ore</td></tr><tr><td>(c)</td><td>Rock salt</td><td>(iii)</td><td>Sulphide ore</td></tr><tr><td>(d)</td><td>Epsom salt</td><td>(iv)</td><td>Carbonate ore</td></tr></tbody></table>

Question 93 :
In Down's process for the extraction of&#160;sodium, the melting point of $NaCl$ is lowered&#160;from $803^{0}C$ to $600^{0}C$.<br/><br/>Choose the correct statement(s) regarding this.<br/>a) It is done in order to avoid vapourisation of metallic&#160;sodium.<br/>b) It is done in order to avoid corrosive action of&#160;sodium and chlorine on the vessel at the high&#160;temperature.<br/>c) It is done&#160;by mixing sufficient amounts of $CaCl_2$.<br/>