One of the advantages of classifying elements systematically in the Periodic Table of Elements is

• Making it easier for the scientists to choose atoms

• Knowing the number of neutrons in an element

• Predicting the chemical characteristics of an element

• Identifying the scientist who discovered the element

Which of the following statements is true about the Periodic Table of Elements?

• There are 18 Groups and 8 Periods in the Periodic Table of Elements

• Groups are the horizontal rows of elements

• Periods are the vertical columns of elements

• Elements that have the same number of valence electrons are arranged in the same group

Scientists who have contributed to the classification of elements in the Periodic Table are as follows except

• John Newlands

• Lothar Meyer

• Anton Mendeleev

• Henry Moseley

In the Periodic Table of Elements, R and S are placed in the same group. If the proton number of R is 19, what is the electron arrangement of element S?

• 2.8.1

• 2.8.7

• 2.8.8.2

• 2.8.8.5

The size of atoms in Group 18 get larger down the group. This is caused by

• the increase in the number of electrons

• the decrease in melting point and boiling point of the elements

• the increase in solubility rate in water

• the increase in the number of shells filled with electrons

During a chemical reaction, every alkali atom in Group 1

• releases one valence electron to achieve duplet or octet electron arrangement

• releases two valence electrons to achieve duplet or octet electron arrangement

• releases three valence electrons to achieve duplet or octet electron arrangement

• releases four valence electrons to achieve duplet or octet electron arrangement

The reactivity of Group 17 elements decrease down the group. This is caused by

• the decrease in atomic size down the group

• the decrease in boiling point and melting point

• the colour of element getting darker down the group

• the attractive force of the nucleus on the electron getting weaker

The change in physical properties of the elements across Period 3 from left to right in the Periodic Table of Elements is due to

• the increase in proton number

• the increase in the radius of atoms

• the decrease in electronegativity

• the change in physical state from gas to liquid and finally to solid

This element has two or more oxidation numbers and forms compounds that have different colour. This element is

• metalloid element

• amphoteric element

• transition element

• alkaline earth metal element

Name the element that is used as a catalyst in the Ostwald Process to produce nitric acid.

• Nickel

• Platinum

• Metal

• Vanadium(V) oxide