on given 3. Use the kinetic theory to explain each observation gis a. Wax melts near the flame of
a burning candle, ay be converted into ice cubes in a fre b. Liquid water m c. Ginger ale flows to
match the shape of the glass.ezer d. Water gradually evaporates from a swimmin e. Water vapor
condenses inside house windows Pool days. f Snow gradually disappears, even when the
temperatu remains below freezing. Solids and liquids cannot be compressed as muclh g. as gases.
4. What is the major difference between a crystal and an amorphous solid? 5. Assume that the
particles in table salt (NaCl) vibrate just as forcefully as the particles in lead (Pb). Explain why
table salt remains a solid at 500 °C while lead exists as a liquid. 6. When heat is being removed
from a liquid, why does the temperature of the liquid at its freezing point remain constant until
all of the liquid freezes?
Solution
3.(a). Wax has a very low melting point. Thus it melts as soon as it reaches its required
temperature which is not very high. But wax is also a very poor conductor of heat. Thus except
for its tip, which is up in flames, other parts are not subjected to such high temperatures to melt
it. Thus it burns near its flame in its liquid state to form CO2 and H2O during combustion to give
heat and light which steadies the burning.
(b). The temperature in freezer is below the melting point. Thus when water is put in a freezer,
the molecules form H bonds with one another to create a macromolecule which is bigger in size
than regular water. Thus they form solid.
(C). Ginger ale is a liquid. It has intermolecular H-bonds which is weaker than Van-der Waal or
dipole forces of solids. But is strong enough to keep the molecules in a place. Thus it flows to
take the shape of the container.
(d). The water molecules of the surface are held by only forces from below the molecules. Thus
they have higher energy than bulk molecules. Thus as soon as they recieve the threshold energy
to escape, they escape Inthe form of evaporation.
(e). The temperature outside home is very low during winters. Thus water vapour condenses to
form water on outer side of windows. I think the question of yours is wrong. Water is formed
outside, not inside the window.
(f). Snow formed outside contain various impurities. Thus their freezing point is lowered. Thus
snow melts even when temperature is 0°C.
(g). The intermolecular gap between molecules is much higher in gases than in liquids and
solids. Thus they cannot be compressed as much.
4. A crystal has regular arrangement of atoms and is a long range order. While amorphous solids
are of short range order and they also lack periodic regular arrangement of atoms.
5. The bond energy of atoms in lead is lower than that of NaCl. Also the molecules are far apart.
Thus even after energy being supplied NaCl atoms are still rigid due to regular periodic
arrangement of NaCl in a crystal structure.
6. This extra energy is used to break the bonds of all the the molecu.
on given 3. Use the kinetic theory to explain each observation gis a..pdf
1. on given 3. Use the kinetic theory to explain each observation gis a. Wax melts near the flame of
a burning candle, ay be converted into ice cubes in a fre b. Liquid water m c. Ginger ale flows to
match the shape of the glass.ezer d. Water gradually evaporates from a swimmin e. Water vapor
condenses inside house windows Pool days. f Snow gradually disappears, even when the
temperatu remains below freezing. Solids and liquids cannot be compressed as muclh g. as gases.
4. What is the major difference between a crystal and an amorphous solid? 5. Assume that the
particles in table salt (NaCl) vibrate just as forcefully as the particles in lead (Pb). Explain why
table salt remains a solid at 500 °C while lead exists as a liquid. 6. When heat is being removed
from a liquid, why does the temperature of the liquid at its freezing point remain constant until
all of the liquid freezes?
Solution
3.(a). Wax has a very low melting point. Thus it melts as soon as it reaches its required
temperature which is not very high. But wax is also a very poor conductor of heat. Thus except
for its tip, which is up in flames, other parts are not subjected to such high temperatures to melt
it. Thus it burns near its flame in its liquid state to form CO2 and H2O during combustion to give
heat and light which steadies the burning.
(b). The temperature in freezer is below the melting point. Thus when water is put in a freezer,
the molecules form H bonds with one another to create a macromolecule which is bigger in size
than regular water. Thus they form solid.
(C). Ginger ale is a liquid. It has intermolecular H-bonds which is weaker than Van-der Waal or
dipole forces of solids. But is strong enough to keep the molecules in a place. Thus it flows to
take the shape of the container.
(d). The water molecules of the surface are held by only forces from below the molecules. Thus
they have higher energy than bulk molecules. Thus as soon as they recieve the threshold energy
to escape, they escape Inthe form of evaporation.
(e). The temperature outside home is very low during winters. Thus water vapour condenses to
form water on outer side of windows. I think the question of yours is wrong. Water is formed
outside, not inside the window.
(f). Snow formed outside contain various impurities. Thus their freezing point is lowered. Thus
snow melts even when temperature is 0°C.
(g). The intermolecular gap between molecules is much higher in gases than in liquids and
solids. Thus they cannot be compressed as much.
4. A crystal has regular arrangement of atoms and is a long range order. While amorphous solids
are of short range order and they also lack periodic regular arrangement of atoms.
2. 5. The bond energy of atoms in lead is lower than that of NaCl. Also the molecules are far apart.
Thus even after energy being supplied NaCl atoms are still rigid due to regular periodic
arrangement of NaCl in a crystal structure.
6. This extra energy is used to break the bonds of all the the molecules before they can recieve
further energy to jump to the next phase. Thus temperature remains constant till all the molecules
have not got the required threshold energy.
