Q6. Short Q/A: (3*2=6M)
1)Define.. Latent heat of fusion, Sublimation
2)Give Dalton's symbols of elements -Nitrogen, Copper, Carbon, Oxygen
3)Explain the factors affecting Evaporation.
Q7. Short Q/A: (3*3=9M)
1)Write difference between three states of matter.
2)Calculate the number of ions present in 0.051g of Aluminium oxide.
3)Draw Chemical formulae for...
Hydrogen chloride
Magnesium hydroxide
Q8) Long Q/A: (2*5=10M)
1) a) What are the Dalton's postulates? (3M))
b) Define Valency. Write it for Carbon and Helium. (2M)
2) a) Differentiate between Boiling and Evaporation. (3M)
b) What is molecule? Give its types. (2M)
Answers
Answer:
Ans 1. The amount of heat transfer required to cause a phase change in unit mass of a substance at constant volume and temperature is called as latent heat. ... The latent heat of sublimation (lsub) is the amount of heat transfer required to convert unit mass of solid into vapour of vice versa.
Ans 3. The surface area and rate of evaporation are proportional to each other. Humidity: The rate of evaporation decreases with an increase in humidity. ... Wind speed: Increase in wind speed results in increased evaporation. Wind speed and rate of evaporation are proportional to each other.
Q7
ans1. Matter can exist in one of three main states: solid, liquid, or gas. Solid matter is composed of tightly packed particles. ... Gaseous matter is composed of particles packed so loosely that it has neither a defined shape nor a defined volume. A gas can be compressed.
Answer:
Q1) Latent heat of fusion
The enthalpy of fusion of a substance,also known as latent heat of fusion is the change in its enthalpy resulting from providing energy, typically heat, to specific quantity of the substance to change its state from a solid to a liquid, at constant pressure.
Sublimation:
The latent heat of sublimation is the energy required to convert a given quantity of solid into vapour, without any changes in temperature.