prep 2 , .lesson 1

In Mendeleev's periodic table, elements are classified in an ascending order according to their.......................

• Atomic weight

• Atomic number

In Mosely's periodic table, elements are classified in an ascending order according to their..............................

• Atomic weight

• Atomic number

The scientist ............. ...... discovered the main energy levels of the atom

• Mendeleev

• Rutherford

• Bohr

• Mosely

......................is located on the left side of the periodic table.

• S-Block

• P_Block

• d_Block

• F_Block

d-block is located on the ............... of the periodic table

• Right

• left

• Middle

• Below

The transition

elements start to appear from the beginning of the............... Period

• First

• second

• Third

• fourth

The elements which occupy the middle block (d) in the periodic table are called

......................elements

• AAcidic

• Alkali

• Transition

• Noble

Lanthanides and actinides are located in the........................block

• S

• P

• D

• F

The element whose atomic number (18) is...........................

• transition element

• inert gas.

• Metallic element

• Halogen element

The element _(12X) is located in ....................... of the periodic table.

• period (2) and group (2A)

• period (2) and group (3A)

• period (3) and group (2A)

• period (3) and group (4A)