Question Text
Question 3 :
The fuel used as aviation fuel in jet aeroplanes is a special grade of _________ .
Question 7 :
Which coal is the generally the primary source of coke production?
Question 8 :
_________ are the primary reason for finishing materials ( resources ) fastly.
Question 22 :
Most balloons, tyres and footballs are made-of rubber. This is because rubber is:
Question 23 :
Metals generally have _________ number of electrons in their valence shell.<br>
Question 25 :
In the following elements identify the element that is relatively strong?
Question 26 :
Assertion: Metals like Na, K, Ca and Mg are never found in their free state in nature.
Reason: Metals are very reactive elements. So, it combine with other non metal to complete its octet. Metals like Na, K, Ca and Mg are never found in their free state in nature.
Question 32 :
Which element can form positive ions by the loss of electrons?
Question 35 :
Mark the correct statement:<br/>(a) Sodium metal forms positive ions.<br/>(b) Magnesium forms $Mg^{2+} ions$.<br/>(c) Aluminium forms negatively charged ion.
Question 36 :
State whether true or false :<br/>Coins can be made up of pure metals.
Question 41 :
Non-metals which are present in fertilizers and enhance the growth of plants is:<br/>
Question 47 :
Which of the following metals were used as money in ancient times?<br>
Question 49 :
On addition of which metal, copper sulphate solution (blue colour) will be changed to colourless solution?