EduNinja
[Maximum number: 1]

Which of the following is a consequence of the adhesive properties of water?

A

Stable temperatures of aquatic environments

B

Water movement by capillary action in soil

C

Transport of dissolved nutrients in blood plasma

D

Cooling effect of sweating

[Maximum number: 3]

To investigate the thermal properties of water, students placed hot water in two thin plastic cups and measured their rate of cooling. The sides of one cup were covered with tissue paper soaked in hot water; the other cup was left uncovered. The temperature was recorded with a thermometer every 4 minutes for 20 minutes. The temperature in the laboratory was 18C18^{\circ} \mathrm{C}.

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(a)

Explain, with reference to the thermal properties of water, how this experiment helps demonstrate how humans respond to overheating.

[ 3 ]
[Maximum number: 1]

Which symbol indicates the polarity of the oxygen atom in the water molecule?

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A

δ+\delta+

B

δ\delta-

C

+

D

-

[Maximum number: 1]

What describes bonding within a water molecule?

A

Hydrogen bonding due to transfer of electrons

B

Double bonds due to equal sharing of electrons

C

Non-polar covalent bonding due to equal sharing of electrons

D

Polar covalent bonding due to unequal sharing of electrons

[Maximum number: 1]

The photograph shows a pond skater.

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Which property of water allows the insect to walk on water?

A

Adhesion

B

Capillarity

C

Surface tension

D

Transparency

[Maximum number: 1]

Which characteristic of the ringed seal (Pusa hispida) is a consequence of the thermal conductivity of water?

A

Streamlined body

B

Sharp teeth

C

Blubber (layer of fat)

D

Lungs

[Maximum number: 1]

Why is sweat a good coolant for the body?

A

The arterioles that transfer water to sweat move closer to the skin surface when it is hot.

B

Breaking H bonds between water molecules in sweat requires energy from body heat.

C

Sweat contains minerals such as sodium chloride.

D

Sweat is non-polar.

0