What property of water helps living or8n r.myz1 jxbhaf:+ut*ku96pganisms maintain their internal body temperatureuzhab*:9t1pf nxy6 m8+j kur.?

  Which of the following is not i5p2 c;ts-oa lsoluble in water?

  What substances are attracted to water and form intermolecn xi z rocp1b14n::yc6e0j oy;ular bonds with water mo c1n6yo 1i;jpxnbyzo c::4e0r lecules?

  Which of the following is a reason for the retention of water on t k8517drvj epEarth?

  What is the most accepted theory for thg4wc p/nc;)fv/ su86erq e2 swe origin of water on Earth?

  What intermolecular bond is responsible f+gjp19duku7 y0 a8 ,kny4qeiror water's cohesive, adhesive and thermal properties?8y, dreu7y pniqj1uk04a gk +9

1.Outline how hydrogen bonds form between 0 1a wrt*6gqw0j4gvthwater 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 8w36 ef 0omz ygqa lk+)j:j2qwu)ayz(marine animals such as the ringed seal (Pusa hispida) to stay afloat in wa 6qjljyw) 2yg+auze8( f03oqzk maw:) ter without expending large amounts of energy?

  The cohesive and adhesive properties of water allow xylem vessel-n d4 s ;ettuemyve9q1d4y//zs to transport waterte9-n1 e dym/4sq dz4u/e; vyt inside 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 com56m;+im5zh) xf 3 :h qf8,mzsrlogklnsidered to be in ‘The Goldilocks 6g5 z3mmrh5x:hl k,l +8 isz)fmm;q fozone’, but Saturn is not?

  Which of the following statements about the dipolari1g64ecf ttpa *ty of the water molecule are aeg *6tcp1f4 ttrue?
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 no; +5teltmpgwi xw /x94t a reason that scientists look for the presence of water on planets as a sign o+l twm9gxp / ;itwe45xf extraterrestrial life?

  Which term to describe a property of water is matched to its correct 4h.boeof m (/qdefinition?o. h4qfbm (e/o

  The image shows a water strider (G. lacustris) 06 rg f u)3pqs2n-q (kb;ges dfvi:en6on the surface of a pond. What pr- ndqe0kqpu(3s si2egrv ; b66):gnffoperty of water is not depicted in the image?

Below is a picture ofdz*v u a(jl;f: a water strider (Gerris 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) that lives in the 7llpo6+5 ihaook57ilih 34h ojm;ez a-z**t u 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 effects of household detergents ona53c:gzmrqyns*9d30gm6m zs aquatic habitats. Scientists tes*msq35magzy0r d :m6ns9 zcg3 ted the effect of different household detergents on the surface tension of water in order to better understand the impact they may 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 is not a real-life examm5 -+ 44ohx0dv tskstj( kjb.mple of adhesion?

The image shows a cross-section of the vascular tissue of a woody dicot 2k /(hprnqu ro4xa s8 rb;; ia(u3j8bostem, showing the annual rings of phloem and xylkjrabnb;p32rou i(r x;( 4 ha8oqus/ 8em.


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 (Gak+d1n6 zq hyu:via arctica) is a bird that lives near large bodies of z qhnd+y:u 1k6water in cold climates. Which of the following is a correct description of how the properties of water may make winter temperatures more moderate for the black-throated loon?

  Which of the following statement(s) about the +)xdtx1yq md g8vvv*2role of water as a solvent is corre8xy gq)xv 1+v*d2dtm vct?

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 a sr4e3sue xl w6vw2 r*gxy ;s tg-or5j0*tem from a plant in the Pinus genus. Xylem vert06 jwglyrrx-2wso5s4 g3 ue* v *xe;ssels are clearly 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 similar to ours, w7xsitu h 1+l;h;1z rtags7j-vdz*: nqhere five planets orbit ahjg z d;u qt17shszl r7:+nx-;1v*a it central 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 how water has facilitated thex/hptb6 d 53wb evolution ob5ph3w/b x6 tdf life on Earth?