Question Text
Question 1 :
Which of the following is the correct set of elements to Dobereiner's triads ?
Question 2 :
The first attempt to classify elements systemically was made by :
Question 3 :
Which element has a dicey position in the modern periodic table?
Question 4 :
The number of metalloids in the modern periodic tables are :
Question 5 :
An element belongs to the 3rd period and Group II of the periodic table.<br/>Name of the element is ________.
Question 6 :
The law of triad is applicable to a group of :<br/>
Question 7 :
In Mendeleev's periodic table few elements that are chemically similar are placed in the same groups.<br/>
Question 8 :
Mendeleev arranged the elements in increasing order of their atomic masses and according to their physical properties.<br/>
Question 10 :
An element which is a soft and reactive metal is :<br/>
Question 14 :
All the elements in a group in the periodic table have the same:<br/>
Question 15 :
An element $X$ (atomic number $17$) reacts with an element $Y$ (atomic number $20$) to form a divalent halide.<br/><br/>Element X is : <br/>
