Account for the following
(a) The temperature of water remains constant
during boiling.
(b) Evaporation is a surface phenomen.
(c) The spaces between the constituent particles
are maximum in gases.
(CBSE Sample Paper 2009-10)
Answers
Answer:-
(a) The temperature of water during boiling
remains constant. This is because the heat
supplied is used up in changing the state from
liquid water to water vapour by breaking
the forces of attraction. As a result, there is
no change in temperature till all the water
evaporates.
(b)The particles on the surface gain energy from
surrounding which increases their kinetic
energy. As a result, the particles of energy higher
than intermolecular forces of attraction leave the
surface and become water vapour and go into the atmosphere. Thus, this is a surface phenomenon because the particles of a liquid present on the surface gain energy and leave the surface.
(c) The attractive forces between the constituent
particles are weakest in gases. Therefore,
the particles are very loosely packed and
the intermolecular spaces between them are
very large. Therefore, the spaces between the
constituent particles are maximum in gases.
Answer:
Answer:-
(a) The temperature of water during boiling
remains constant. This is because the heat
supplied is used up in changing the state from
liquid water to water vapour by breaking
the forces of attraction. As a result, there is
no change in temperature till all the water
evaporates.
(b)The particles on the surface gain energy from
surrounding which increases their kinetic
energy. As a result, the particles of energy higher
than intermolecular forces of attraction leave the
surface and become water vapour and go into the atmosphere. Thus, this is a surface phenomenon because the particles of a liquid present on the surface gain energy and leave the surface.
(c) The attractive forces between the constituent
particles are weakest in gases. Therefore,
the particles are very loosely packed and
the intermolecular spaces between them are
very large. Therefore, the spaces between the
constituent particles are maximum in gases.