What property of water helps living organisms maintainweo - jm,n 9:1via.3hpvlg)-ph yzil/ their internal body temper ,hj a) i.n geppzm-1-vi hvl9o/y3wl:ature?

  Which of the followingr0q *ov;enrf gf 3*pf1 is not soluble in water?

  What substances are attracted to water and form ingp h t7ym9anfq (.beusbr +(:2termolecular bonds with water t: bgpsyu(m +2hnf q7 a9rb(.emolecules?

  Which of the followin dqz1+oqkh3uk wm*/egx-;/ pm4m m-meg is a reason for the retention of water on Earth?

  What is the most accepted theory for the origin of;h.rgd5kjq qn v0gp 10es*nh4 water on Earth?

  What intermolecular bond is responvm.x5 1l1huva sible for water's cohesive, adhesive and thermal h1l1vmu 5a.xvproperties?

1.Outline how hydrogen bonds form bea9b qv,+rqtpfa-x6q+d ;m9i rtween 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 wata5*-kg0sov,ek wo0q dp bq +(yer enables marine animals such as the ringed seal (Pusa hispida) to stay afloatb+gy0k (5s wpoe,q 0 a*-kovqd in water without expending large amounts of energy?

  The cohesive and adhesivego0q or+hlm gn07q3d+ properties of water allow xylem vessels to transport water iqh gonl07 orq3 m+0+gdnside 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 consf 5- cc:pw 6lsavi(a+widered to be in ‘The Gol casw- l56vaic:w +f(pdilocks zone’, but Saturn is not?

  Which of the following statements about the dipolarity of the wfrn6de u *n niv,055:5dgv tvwater molecule are5,vng50wvi*5dutn :df n6e vr true?
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 reasong;q382: bniid kto0pl a:bq .q that scientists look for the presence of water on planets as a sign of extraterrestrial life?2 b:akd qi ;i:lg.q3tno80qbp

  Which term to describe a property of water is matched to its correct defikwuzq-lyndh ,24;v s1nition?vuzdl2wy-n; hk q ,1s4

  The image shows a water strider (G. lacustso 7z;02gqg+mrtit h1ris) on the surface of a pond. What prope tg2hg7it1mos ;q0z+rrty of water is not depicted in the image?

Below is a picture of a water jbw7.(h js q3dstrider (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 hir/-e j49 7xgf3q hnd4a2onsgospida) 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 carr : r3ed pavzyzgu-yvb- n giv):v5)y2;ied out into the effects of household detergents on aquatic habitats. Scientivay2dg:3vry;-e vu5 pn iyzgzb v )-):sts tested 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 example of adhesio/fquf2n-qlrjsh56)hf j6b x7 9mols.n?

The image shows a cross-section of the vascular tis)no0 8pmu n ,mx4bsv5:g2nnrk sue of a woody dicot stem, showing the annual rings of phloem and xylem. 2 r8svmo nn)mxp04n: ng 5,buk


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 bia:ip 7dc wt52ard that lives near large bodies of water in cold climates. Which of the following is a cc:adp 57taw2 iorrect 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 role of water ztb45muy; d d5cut 1b6as a solvent is correct4yzm6c d u1d;b55tbt u?

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 stem fro0+3mjwcla d5qm a plant in the Padwj0 q m3c5+linus genus. Xylem vessels 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, where fivek1y b)b -yu6dw planets orbit a cenw6 d ub)1ky-ybtral 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 stateme 3tzi0 *xs8ny s(jxx +7d:lpxxp d.ia4nts explains how water has facilitated the evolution.+i*08j xzxd4pax(x3s y dl xt i7p:ns of life on Earth?