3.1.3.2 Nature of covalent and dative covalent bonds

Question 1

why the bonding in nitrogen oxide is covalent rather than ionic

Answer 1

Small electronegativity difference

Question 2

how the bond between ammonia and boron trichloride is formed

Answer 2

Lone pair / both electrons / 2 electrons / electron pair on N(H3) is donated to B(Cl3)

Question 3

the type of bond formed when PH3 reacts with H+ and explain how this bond is formed

Answer 3

Co-ordinate/dative
Both electrons/ lone pair (on P/PH3)
Shares/donated from P(H3)/ to H(δ+)

Question 4

AlCl3 + Cl– → AlCl4 – Explain how this co-ordinate bond is formed

Answer 4

Electron pair or lone pair donated

From chloride ion to Al or AlCl3

Question 5

name of the type of crystal structure shown by silicon dioxide (SiO2)

Answer 5

Macromolecular / giant covalent / giant molecule

Question 6

State the type of bond between Br and F in BrF3 and state how this bond is formed.

Answer 6

Covalent
Shared pair(s) of electrons / one electron from Br and one electron from F

Question 7

the type of bond formed when H+ ions react with H2O molecules. Explain how this type of bond is formed in the H3O+ ion

Answer 7

Dative (covalent)/coordinate

Lone) pair/both electrons/two electrons on O(H2) donated (to H+ ) OR pair/both electrons come from O(H2

Question 8

how the bond between ammonia and boron trichloride is formed

Answer 8

Lone pair / both electrons / 2 electrons / electron pair on N(H3) is donated to B(Cl3)

Question 9

the type of bond that is formed between the PH3 molecule and the H+ ion. Explain how this bond is formed.

Answer 9

Coordinate / dative

Pair of electrons on P(H3) donated (to H+)

Question 10

Definition: covalent bond

Answer 10

shared pair of electrons

Question 11

Name the type of bond formed when PH3 reacts with H+ and explain how this bond is formed.

Answer 11

Co-ordinate/dative
Both electrons/ lone pair (on P/PH3)
Shares/donated from P(H3)/ to H(δ+)

Question 12

how this co-ordinate bond is formed

AlCl3 + Cl– → AlCl4 –

Answer 12

Electron pair or lone pair donated

From chloride ion to Al or AlCl3

Question 13

A bond in can be represented by H → Al Name this type of bond and explain how it is formed.

Answer 13

Dative (covalent) or coordinate
Lone pair or non-bonding pair of electron or both e–
Donated from H– to Al or shared between H and Al

Question 14

the type of bond represented in the diagram by N—H

Answer 14

Covalent

Question 15

e the type of bond represented in the diagram by N→H

Answer 15

Co-ordinate

Question 16

In terms of electrons, explain why an arrow is used to represent this N→H bond

Answer 16

Both / two / pair electrons come from nitrogen

Question 17

Fluorine reacts with bromine to form liquid bromine trifluoride (BrF3). State the type of bond between Br and F in BrF3 and state how this bond is formed.

Answer 17

Covalent
Shared pair(s) of electrons / one electron from Br and one electron from F

Question 18

State the type of bond formed between the N atom and the B atom in F2HNBF3. Explain how this bond is formed.

Answer 18

Coordinate / dative covalent / dative

Lone pair / both electrons/ 2 electrons on N(HF2) donated (to BF3)