G8 elementsclassification

Mendeleev's table contain........... element

• 76

• 67

• 118

mendeleev arrange the element with similar prosperities in vertical column called .........

• period

• table

• group

mendeleev arrange the elements according to the increase of their .......

• atomic numbers

• no. of protons

• atomic mass

GR: mendeleev had to make disturbance in the ascending order of atomic mass of some elements

• to put them in groups that suit their properties

• to make it easy to study

• to make balance in the table

mendeleev had to deal with isotopes as different elements

• duo to they have similar atomic masses

• duo to they have similar atomic numbers

• duo to they have different atomic masses masses

the elements that have the same atomic no but differ in atomic weight called ..................

• isobars

• isomers

• isotopes

GR: mendeleev make only 67 cards to classify elements

• because there are only 67 element in the earth

• because there are only 67 element discovered till now

• because there are only 67 element discovered in his time

GR: mendeleev left vacant in his table

• to make it easy to deal with the table

• to put anther chemical compounds in this gaps

• because he predict the discovery of a new elements

from the advantages of Mendeleev's table he make ...................of some elements

• correction of atomic masses

• correction of atomic numbers

• discovery

Mendeleev's periodic table considered ........................

• the first periodic table for classifying elements

• the last periodic table for classifying elements

• the most accurate periodic table for classifying elements