classification of elements

According to Moseley , a straight line graph is obtained on plotting:

• The frequencies of characterstic line graph

• The square of the frequencies of charcterstic X-rays of elements against their atomic numbers.

• The square root of the frequencies of charactersics X-rays of elements against their atomic numbers.

• The reciprocal of the frequencies of characterstic X-rays of elements against their atomic numbers

The atomic volume was chosen as the basis of periodic classification of elements by :

• Neil Bohr

• Mendeleev

• Lother Meyer

• Newland

If A , B and C are the three element of Dobereiner's Triad and atomic weight of A and B are 7 and 15 respectively then the atomic weight of C is :

• 1

• 11

• 23

• 25

According to the Lother Meyer's curve which of the following statements is incorrect?

• The element having similar properties will occupy the same position in the curve

• Alkaline earth metals are at the peaks of the curve.

• Halogens are at ascending part of the curve

• The atomic volume of the element in a period initially decreases and then increases

Eka- aluminium and Eka- silicon are known as:

• Gallium and germanium

• Aluminium and silicon

• Iron and sulpur

• Proton and silicon

Which of the following set of elements obeys New lands octave rule?

• Na, k, Rb

• Cl, Br, I

• Be, Sr, Can

• B, Al, Ga

Am element whose IUPAC name is ununtrium (Uut) belongs to :

• S-block

• p-block

• d-block

• transition element

The elements with atomic number 117 and 120 are yet to be discovered. In which group would you place these elements when discovered?

• 17, 2

• 16, 4

• 15, 3

• 18, 2

Which are correct match?

1. Eka silicon-Be

2.Ska aluminum-Ga

3.Eka manganese-Tc

4.Eka boron-Sc

• 2, 3 and 4

• 1 , 2

• 1 and 4

• All of these

Which one of the following ions has the highest value of ionic radius?

• O^-2

• B⁺³

• Li⁺

• F^-