water

Question 1

what’s specific heat capacity

Answer 1

energy required to raise one kg of the material by 1 degree celcius

Question 2

what’s specific latent heat

Answer 2

amount of energy required to change the state of one kg of a material without changing its temperature.

Question 3

name 5 functions of water

Answer 3

reactant, solvent, transport medium , temperature control . habitat

Question 4

how is water a reactant

Answer 4

involved in many chemical reactions

Question 5

how is water a solvent

Answer 5

substances can dissolve in it eg the cyptoplasm

Question 6

how is water a good transport medium

Answer 6

since its a good solvemy , solutes can be easily transported.

Question 7

how does water have good temperature control

Answer 7

due to it high specific heat capacity and high latent heat of vaporisation.

Question 8

how is water a good habitat

Answer 8

as it helps with temperature control , is a solvent and becomes less dense below 4 degrees Celsius when its frozen , aquatic organisms can live in it.

Question 9

how much of the surface of earth does water make up

Answer 9

3/4ths

Question 10

is water a polar molecule

Answer 10

yes

Question 11

define polar

Answer 11

When a molecule is polar, it means its positive and negative electrical charges are unevenly distributed so part of the molecule is partially positive, while part is partially negative

Question 12

how is water polar

Answer 12

the oxygen atom attracts more electrons (very electronegative)due to it having more protons than the hydrogens , making the hydrogens slightly positive and the oxygen slightly negative.

Question 13

what are hydrogen bonds

Answer 13

bonds between water molecules , bond easily due to slightly negative hydrogen being able to bond to slightly negative oxygen, hydrogen bonds also contribute to the properties of water.

Question 14

properties of water : what is adhesion

Answer 14

water molecules stick to other substances

Question 15

properties of water : what is cohesion

Answer 15

water molecules stick to each other

Question 16

how does cohesion help organisms

Answer 16

allows water striders to skate on water since cohesion contributes to surface tension(water has alot of this)

Question 17

what’s surface tension

Answer 17

property allowing liquid to resist external force

Question 18

how do cohesion and adhesion help water travel up a plant

Answer 18

water molecules stick to xylem walls via adhesion and then stick to each other via cohesion in order to bring water up a plant against gravity.

Question 19

properties of water : what is a super solvent

Answer 19

water can dissolve many other molecules ESPECIALLY polar molecules and ionic compounds.

Question 20

how is water useful for organisms as a solvent

Answer 20

many organisms use water a solvent for processes. A main component for bodily fluids is also water.

Question 21

properties of water : what happens to water below 4 degrees Celsius.(ice as an insulating layer)

Answer 21

expanding , becoming less dense and acting as a insulating layer. Hydrogen bonds don’t break and remake as often when frozen , molecules are set into a lattice.

Question 22

how does ice as an insulating layer help organisms

Answer 22

it protects aquatic organisms underneath , they do not freeze and are able to swim

Question 23

properties of water : what is high specific heat capacity for water

Answer 23

water does not fluctuate in temperature which is stabilising for aquatic organisms.

Question 24

properties of water: water has evaporative cooling

Answer 24

water moves faster when heated and more likely to change into gas , so when they leave their heat and energy is no longer on your body.

Question 25

do water molecules form strong hydrogen bonds between each other

Answer 25

no , they are weak ,weaker than a covalent bond

Question 26

how do polymers and hydrogen bonds relate

Answer 26

in some polymers thousands of them are formed between chains of monomers.

Question 27

how do hydrogen bonds help biological molecules

Answer 27

stabilises their structure.

Question 28

why is water a good solvent

Answer 28

it is a polar solvent and it can dissolve polar molecules and ionic compounds , polar molecules cant dissolve non polar.

Question 29

what happens to water in a solid state

Answer 29

when water reaches a solid state hydrogen bonds become more stable , breaking and a reforming less, arranging water molecules further from each other

Question 30

how does water in a solid state explain “why does ice float on water”

Answer 30

water in a solid state expands and becomes less dense than water, making it float

Question 31

do the exam questions on the water ppt