Covalent Bonding in Physiogically Important Molecules

Question 1

Atom put in middle of Lewis diagrams

Answer 1

Lowest electronegativity (Hydrogen as exception)

Question 2

Valence Electrons Def.

Answer 2

Electrons in the outermost shell of an atom

Question 3

Atom(s) to 1st reach octect rule in Lewis Diagram

Answer 3

Most electronegative

Question 4

How octect rule is (sometimes) reached in least electronegative atoms

Answer 4

Forming double/triple bonds

Question 5

Resonance Def.

Answer 5

2+ Lewis diagrams can be drawn for atom

Question 6

Isoelectric Def.

Answer 6

Same number of valence electrons and same connectivity

Question 7

Paramagneticism Def.

Answer 7

Substance with lone electrons that weighs heavier in an electromagnetic Field

Question 8

Limitations of Lewis diagrams

Answer 8

Can’t explain paramagneticism in O2 while molecular orbital theory can

Question 9

Nitric Oxide

Answer 9

lowers blood pressure, relaxes cardiovascular tissue, acts as a neurotransmitter and acts as an anti-microbial defence

Question 10

Radicles Def.

Answer 10

Reactive chemical species with unpaired electron

Question 11

An example of a free radical

Answer 11

Superoxide

Question 12

Disproportionation Def.

Answer 12

A redox reaction where an element is in 1 redox state both oxidised and reduced

Question 13

Enzyme for disproportionation

Answer 13

Superoxide Dismutase

Question 14

Reactive Oxidation in Body

Answer 14

Oxidise cholesterol, oxidise unsaturated fatty acids and membrane lipid preoxidation

Question 15

Oxidisable Cellular Components Examples

Answer 15

NADH, NADPH, absorbic acid, histidine, proteins and nucleic acids

Question 16

Nitric Oxide

Answer 16

Nerotoxic. Forms peroxynitrite

Question 17

Peroxynitrite

Answer 17

Oxidant and nitrarting agent. Causes damage to parts of cell. Eg DNA

Question 18

Enzyme to reduce effects of NO

Answer 18

seuperoxide dismutase

Question 19

Exceptions to Octet Rule in Lewis Diagrams

Answer 19

group 2A and 3A