1.1- chemistry for life

Question 1

ionic bonding

Answer 1

-involves a metal losing an electron to become a positive ion (cation)
-and a non-metal gaining an electron (anion)
-held together by strong electrostatic forces of attraction

Question 2

covelant bonding

Answer 2

-involves two non-metals achieving full outer shells and becoming more stable by sharing a pair of electrons
-very strong and form neutral molecules

Question 3

The importance of inorganic ions

Answer 3

-most ionic substances exist as negative and positive ions which play a specialised role in individual cells and functioning of organisms

Question 4

important anions- nitrate

Answer 4

-needed in plants for formation of amino acids and therefore proteins
-formation of DNA

Question 5

important anions- phosphate

Answer 5

-needed in all living organisms for formation of ATP and ADP aswell as DNA and RNA

Question 6

important anions- chloride

Answer 6

-needed in nerve impulses and many secretory systems

Question 7

important anions- hydrogen carbonate

Answer 7

-buffers the blood to prevent it becoming too acidic

Question 8

important cations- sodium

Answer 8

-needed in nerve impulses and many secretory systems

Question 9

important cations- calcium

Answer 9

-formation of calcuim pectate for middle lamella between 2 cell walls
-bone formation and muscle contraction

Question 10

important cations- hydrogen

Answer 10

-cellular respiration and photosynthesis
-pumps and systems in organisms
-ph balance

Question 11

important cations- magnesium

Answer 11

-production of chlorophyll in plants

Question 12

the importance of water (3)

Answer 12

1.high specific heat capacity- buffer against rapid temp change meaning a lot of joules of energy needed
2.high latent heat evaporisation- not often lost
2.sweating removes energy
3.hydrolysis and condensation

Question 13

importance of water pt2 (4)

Answer 13

4. transport medium e.g plasmids and oxygen in blood
   5.great solvent- oxygen can dissolve in so organisms can live in it
   6.high cohesion allowing organisms to live on surface
5. adhesive-attracted to other molecules- transport

Question 14

water as a polar solvent

Answer 14

-water is polar molecule
-O- and H+ leads to formation of hydrogen bonds
-shared electrons pulled closer to O2

Question 15

how are hydrogen bonds formed in water

Answer 15

-electrons held slightly closer to the oxygen making water polar
-slightly negative oxygen attracts slightly positive hydrogen in weak electrostatic force (hydrogen bond)
-collectively strong