⬆️ TOP EDUCATION ⬆️
CLASS 9th
CHAPTER 1 MATTER IN OUR SURROUNDINGS
EXTRA IMPORTANT QUESTIONS
AND
ANSWER.
Q1.What is the matter?
Ans1: Matter is anything that occupies space and has mass. It can exist in three states: solid, liquid, and gas.
Q2.Define the term 'evaporation.'
Ans2: Evaporation is the process in which a liquid changes into its gaseous state at any temperature below its boiling point. It occurs from the surface of the liquid.
Q3: Explain the process of sublimation.
Ans3: Sublimation is the process in which a solid directly changes into its gaseous state without passing through the liquid state. Example: Camphor, ammonium chloride.
Q4.What is the effect of pressure on the boiling point of a liquid?
Ans4:Increasing the pressure on a liquid increases its boiling point, while decreasing the pressure lowers the boiling point.
Q5.Why do gases exert pressure on the walls of the container?
Ans5:Gases exert pressure because the gas particles are in constant random motion. When they collide with the walls of the container, they exert a force per unit area, which results in pressure.
Q6.What is the difference between evaporation and boiling?
Ans6:Evaporation occurs at any temperature below the boiling point, whereas boiling occurs at a specific temperature called the boiling point. Evaporation occurs only from the surface, while boiling occurs throughout the liquid.
Q7.What happens to the kinetic energy of particles during evaporation?
Ans7: During evaporation, the particles at the surface of the liquid gain enough kinetic energy to overcome the attractive forces of the liquid. This results in their conversion into the gaseous state.
Q8, Define the term 'latent heat.'
Ans8:Latent heat is the heat energy absorbed or released during a change of state without any change in temperature. It is further classified into the latent heat of fusion and the latent heat of vaporization.
Q9.Give an example of a solid that sublimes on heating.
Ans9:An example of a solid that sublimes on heating is iodine.
Q10.What is the triple point of a substance?
Ans10:The triple point of a substance is the temperature and pressure at which all three states (solid, liquid, and gas) of the substance coexist in equilibrium.
☆These are some important questions and answers related to Class 9 Science, Chapter 1: Matter in Our Surroundings. I hope they are helpful to you!