kg
N
wength
Mass
Weight
Volume
Density
Pressure
DC
kilogram
newton
cubic metre
kilogram per cubic metre
pascal
kg m
Pa
Exercises
1. Convert the following temperatures to the celsius scale.
(a) 293 K
(b) 470 K
2. Convert the following temperatures to the kelvin scale.
(a) 25°C
(b) 373°C
Give reason for the following observations.
(a) Naphthalene balls disappear with time without leaving
any solid.
(b) We can get the smell of perfume sitting several metres
away.
Answers
1 a) 20 degree Celsius b)197 degree Celsius
2 a)298 k b) 646 k
Explanation:
temperature to Celsius scale
0 degree Celsius = 273 kelvin
a) 293 k - 273 k = 20 degree Celsius
b) 470 k - 273 k = 197 degree Celsius
temperature to kelvin scale
a) 25 degree Celsius + 273 k = 298 k
b) 373 degree Celsius + 273k = 646 k
a) Naphthalene balls disappear with time without leaving any solid.
Naphthalene undergoes sublimation easily i.e., the change of state of naphthalene from solid to gas without the intervention of the liquid state. Thus, naphthalene balls keep on forming naphthalene vapours which disappear into the air with time without leaving any solid.
b) We can get the smell of perfume sitting several metres
away.
Explanation: The process of diffusion is such that the particles from a high concentrated area will move to a less concentrated area. In this case, perfume particles concentrated to where it is applied will move to other less concentrated areas, which allows you to smell it from afar