Which of the following molecules contains the highest number of the lone pairs of electrons ?

• F₂

• CH₄

• CO₂

• H₂O

Which of the elements forming the opposite compound has higher partial negative charge? ……………

•  I

• Br

• F

• Cl

Which of the following choices represents hydrogen cyanide HCN? ……………

• Carbon atom ₆C has one lone pair of electrons.

• Nitrogen atom ₇N has one lone pair of electrons.

• Hydrogen atom ₁H has one lone pair of electrons.

• Nitrogen atom ₇N has two lone pair of electrons

Which of the following is not a type of chemical bonding?

• Metallic

• ionic

• nuclear

The molecule of the element with an electronic configuration 1s² ,2s² ,2p⁶ consist of ……………… atom(s).

• one

• two

• three

• four

What is the number of unpaired electrons in ₇N^3- ion? ……………

• zero

• 1

• 2

• 3

Which of the following compounds its solution is characterized by its ability to conduct electricity?...............

• C₂H₄

• KCl

• CH₄  

• C₂H₆

The molecules of ......... are similar in their stereostructure

• H2O and ClO2  

• BF3 and BeF2

• CH4 and NH3  

• H2O and NH3

In which of the following compounds the angle between the bonds is higher? ……

• CO₂   

• BF₃  

•  CCl₄

•  NF₃

Why is the formula for sodium chloride NaCl , but the formula for magnesium chloride is MgCl2 ?

• Chlorine forms a -1 ion so it requires two magnesium ions to form an electrically neutral compound.

• Magnesium forms +2 ions, so it requires one chloride ion to form an electrically neutral compound.

• Magnesium forms +2 ions, so it requires two chloride ions to form an electrically neutral compound