Water PPT

Question 1

what is cohesion

Answer 1

attraction between particles of the same substance (water is attracted to itself)

creates an inward cohesive force that pulls water molecules at the surface together

results in surface tension

Question 2

what is adhesion

Answer 2

attraction between two different substances

water will make hydrogen bonds with other surfaces such as glass, soil, plant tissues and cotton

capillary action - water molecules will tow each other along when in a thin glass tube

Question 3

properties of water

Answer 3

cohesion
adhesion
high specific heat
less dense as a solid
high heat of vaporisation

Question 4

what is specific heat

Answer 4

amount of heat required to raise 1g of water up by 1 degree C

water resists temperature changes, both for heating and cooling

Question 5

what does water vapour do for the earth

Answer 5

water vapour forms a kind of global blanket which helps to keep the Earth warm.

Heat radiated from the sun warms the surface of the earth and is absorbed and held by the vapour

Question 6

what are the two types of mixtures that involve water

Answer 6

water is usually a part of a mixtures

solutions - substance dissolves in liquid

suspensions - substance suspends in liquid.

Question 7

is water polar

Answer 7

oxygen acts as negative and hydrogens act as positive, so polar

Question 8

capillary action

Answer 8

ability of a liquid to flow against gravity in a narrow space