What property of water helps living organisms maintain (l7 h*erytryi+-gz buc +/+t0falp+ ktheir internal body temperatui+07(ktha+yfpll/c-+rye u* grz bt + re?

  Which of the following is not soluble inybk 2kvhz +q64ucj5w + water?

  What substances are attracted to water and yiydx ,wd4-h,m,cxybf- k 8;nform intermolecular bonds with water moy 84kyb-; icmwx-, hdd,,fxynlecules?

  Which of the following is a(hur ,6cr9sql2jv1 tc reason for the retention of water on Earth?

  What is the most accepted theory for the originuhso8-o: fy1s68urxp*nfl y wqv9i,. of water on Earth?

  What intermolecular bond is responsible for water's coiid -; kbtpye;t*(t 9hhesive, adhesive and thermal propertie( ti;;tt*kp9e- b hydis?

1.Outline how hydrogen bonds form betwee6lyf 1 cs01c.g:a y-knn onw+nn water molecules.

2.State one of the ways how hydrophilic substances interact with water.

3.State one of the ways how non-polar molecules interact with water.

4.Distinguish cohesion and adhesion.

  Which property of water enables marine animals such as the ringed seal (Pusa h ,t23xv( 7bfd8dim )vae1uncrispida) to stay afloat in water without expending lxa78 3fcbvvn,1dure) 2t( i mdarge amounts of energy?

  The cohesive and adhesive properties of water allow xylem vessels to4o1kn0rxuvx2w p py 79 transport water insidryxw o9n p 4vpx7210kue plants.

Which of the following are correct descriptions of how these properties are related to water transport in plants?

  Which of the following is a reason that the Earth is considered to ber)d xpy2ktxc1h -op8/8 mslz*)o5wto in ‘The Goldilocks zone’, but Saturn is nothl-c *o/pmxkty)tsop285xorwz 1 d8)?

  Which of the following statements about the dipolarity of the water molecule ar+g(dx i9b9aj)l3giv pe true? ivjdpxi+)9 g lgba93(
I. Oxygen attracts the shared electrons stronger than hydrogen.
II.Hydrogen atoms are partially negative.
III.The shared electrons spend more time closer to oxygen.

  Which of the following is not a readufjwrtfks1/vn -ae g/r 3-y-. z+cs1son that scientists look for the presence of wa-a/1krtz c+rvsf .-g-nswe/3f ud1yjter on planets as a sign of extraterrestrial life?

  Which term to describe a property of water is matched to its corre bgk: n0s0)wacct definition?ca0:nw)kb g 0s

  The image shows a water strider (G. lacustris) on the surface of a gitwg 5m4p; -sep4 xp8pond. What property of water is not depicted in t g;tppms4 58pw4i-exghe image?

Below is a picture of a water strider (Gerri/f9yw ;qikna3 ;l*- s-af pjqys sp.).


1.Explain why the water strider (Gerris sp.) does not sink.
2.Describe, using an example, the importance of water as a solvent in living organisms.

The image shows a ringed seal (Pusa hispida)5ppt/)cei0jt dngb2 /*7n/8cko yna quf0/da that lives in the Arctic Sea.


1.Distinguish between the physical properties of air and water that allow the seal to mostly live in the sea.
2.Ringed seals glide into the water head first from ice shelves, rather like humans diving into a pool head first. Explain the advantage of entering the water in this way rather than ‘belly-flopping’ into the water.

  An investigation was carried out into the effecto ,uk9f/aaa6c 0 t m6,epmk3xxs of household detergents on aquatic habitats. Scientists tested the effect of different household detergents on the surface tension of water in order to better understand the impact they maa cmxax 0k3m/fou,te6ka,96py have on organisms living on the surface.

A paper clip was folded slightly on one side and rested on the surface of the water, maintained at a constant temperature and contained within a water tank. Drops of detergent solution were slowly added to the water tank until the paperclip sank to the bottom. The volume of detergent solution taken to sink the paperclip was recorded.

Detergent solutions were made by adding 5 ml of detergent to 15 ml of water.


1.Describe the relationship between the volume of detergent solution added and the surface tension of water.

2.1.For the Easy Clean detergent, calculate the mean number of drops of detergent needed to sink the paper clip.
Mean =  ml
2.2.Estimate how many drops of Easy Clean detergent solution it would take to sink 5 paper clips.

3.1.State one variable, other than those given, which would need to be controlled in this experiment in order to achieve a valid result.
3.2.Suggest one method that could be used to keep the water at a constant temperature.
3.3.Explain the importance of maintaining water at a constant temperature.
3.4.Identify one potential source of error in the methodology.
4.Suggest why different numbers of drops of detergent solution were needed to sink the paperclip between each type of detergent.

  Which of the following :t .rtj9 dd 6xa*;nj7fdf 6uzpis not a real-life example of adhesion?

The image shows a cross-section of the vascular tissue ofr6k-l):xl:v7m v 57d hjlko nfhzz7 z- a woody dicot stem, showing the fm6vkvd:l jr7757ohzhl- kz )x z-ln:annual rings of phloem and xylem.


Explain how the properties of water allow it to be transported in the xylem.
Describe a physical property of water, other than those that are important for the movement of water through the plant, that makes water essential for the survival of plants.
Outline why plants cannot use water to transport lipids.
If the temperature drops to -1$^{\circ}$ for a few hours suggest a reason why the water in xylem may not freeze.

  The black-throated loon (Gavia arctica) is a bird that li okow *l4z(o9lves near large bodies of water in cold climates. Which of the following is a correct description of how the properties of water may make winter tek wo 9l4*(oozlmperatures more moderate for the black-throated loon?

  Which of the following statement(s) about the role of water as a sol .;6x8(zfi jz77 o owxeguek5gvent is correct i6u .;gojz xxkw7 z5(eeg8fo7?

I. Salt can dissolve in water because it is hydrophilic
II. Lipids cannot dissolve in water because they are non-polar
III. Cellulose can dissolve in water, as it is able to form hydrogen bonds

  The micrograph below shows the longitudinal cross-section of yc pud hx6y75eyu*, j:a stem from a plant in the Pinus genus. Xylem vessels are clearluyj: 7uc*dxye6 y,p 5hy visible.


The xylem is composed of hollow, tube-like tissues that transport water through capillary action. What property of water explains capillary action?

The diagram shows a solar system very similpu:dow , fnzhaiz2 8k)t6l28 dar to ours, where five planets orbit a central2dzd2u:8p,tkf8 zn o)l iwah6 star.


1.Define the term “Goldilocks zone”.

2.1.Label with the letter R the planet that is least likely to have extraterrestrial life present.

2.2Explain reasons for your answer to part (i).

3.1.Some of the planets in this solar system have water present on them. Suggest where this water might have come from.

3.2.Explain why the planets referred to in part (i) have retained water, whereas others in this solar system have not.

4.Suggest one other biological molecule, other than water, that may be a sign of life on a planet.

  Which of the following statements explains ns4a6gukzf6, how water has facilitated the evolutiukzfs 4 gn,66aon of life on Earth?