a) Convert the following temperature to the Celsius scale.
(i) 293 K (ii) 470 K
b) Why can you smell the perfume of incense stick ?
c) Why does the temperature of a substance remain constant during its melting point or boiling point?
d) Which amongst the following is not matter?
(i). Brick
(ii) Pen
(iii) Time
Give reason.
a) Convert the following temperature to the Celsius scale.
(i) 293 K (ii) 470 K
b) Why can you smell the perfume of incense stick ?
c) Why does the temperature of a substance remain constant during its melting point or boiling point?
d) Which amongst the following is not matter?
(i). Brick
(ii) Pen
(iii) Time
Give reason.
(a)
(i)Temperature in Celsius scale = Temperature in Kelvin scale – 273
⇒ 293 K = 293 K – 273
= 20°C
(ii) Temperature in Celsius scale = Temperature in Kelvin scale – 273
⇒ 470 K = 470 K – 273
= 197°C
b) The particles of the perfume (matter) are not stationary, but are continuously moving. They drift through the air and hence we can smell the perfume.
c) The temperature of a substance remains constant at its melting and boiling points until all the substance melts or boil because the heat supplied is continuously used up in changing the state of the substance by overcoming the forces of attraction between the particles. This heat energy absorbed without showing any rise in temperature is given the name latent heat of fusion/latent heat of vapourisation.
d) Anything that has mass and occupies space can be termed as matter. Amongst the given options, both brick and pen has mass and they occupies space as well. However, time neither has mass nor does it occupies any space. Hence, time cannot be considered as matter.
(a)
(i)Temperature in Celsius scale = Temperature in Kelvin scale – 273
⇒ 293 K = 293 K – 273
= 20°C
(ii) Temperature in Celsius scale = Temperature in Kelvin scale – 273
⇒ 470 K = 470 K – 273
= 197°C
b) The particles of the perfume (matter) are not stationary, but are continuously moving. They drift through the air and hence we can smell the perfume.
c) The temperature of a substance remains constant at its melting and boiling points until all the substance melts or boil because the heat supplied is continuously used up in changing the state of the substance by overcoming the forces of attraction between the particles. This heat energy absorbed without showing any rise in temperature is given the name latent heat of fusion/latent heat of vapourisation.
d) Anything that has mass and occupies space can be termed as matter. Amongst the given options, both brick and pen has mass and they occupies space as well. However, time neither has mass nor does it occupies any space. Hence, time cannot be considered as matter.
