unit 1 lesson 1 prep1 part1

The number of known elements up till now is............

• 92

• 118

• 121

• 211 |

All of these elements are metal solid elements, eXcept ....................

• sodium.

• magnesium.

• mercury.

• aluminium.

All of the following are properties of metals, except.....................................

• they are malleable and ductile.

• they are good conductors of electricity.

• they contain 1, 2 or 3 electrons in outermost shell.

• they are bad conductors of heat.

All of the following are metals, except ---------

• iron.

• oxygen.

• copper.

• sodium.

Oxygen is from .................................

• acids.

• bases.

• metal elements.

• nonmetal elements.

The element which has atomic number 12 is considered from ..........

• metals.

• nonmetals.

• noble gases.

• no correct answer.

When an atom of an element loses one electron or more, it changes into............

• negative ion.

• a positive ion.

• .a neutral atom.

• .no correct answer.

All of the following elements can form positive ions, except..................

• sodium (11Na).

• chlorine (17CI).

• ‘magnesium (12Mg).

• aluminium (13Al).

Which of the following figures represents the structure of sodium ion ? Fig (........ ):

• 
• 
• 
• 

The number of energy levels in sodium ion is.......... the number of energy levels in its atom

• less than

• more than

• equal to

• no correct answer