Matter in Our Surroundings
Q12. Give the best evidence for motion of particles in matter.
Which process provides the best evidence for the particle theory of matter?
Q13. Which property of liquids and gases tells us that their molecules are moving constantly?
Q14. Write the term that is used to describe the mixing of copper sulphate and water kept in a beaker, on its own?
Q15. Name the phenomenon in which particles of two or more substances intermix on their own.
Q16. Name two substances which undergo sublimation.
Q17. Which of the following are matters?
chair, air, love, smell, hate, almonds, thought, cold, cold drink, smell of perfume.
Q18. Name the gas which is supplied in compressed form in homes.
Q19. Name the gas which is supplied to hospitals in cylinders in compressed form.
Q20. Which of the following is highly compressible?
Q21. Suggest a method to liquefy atmospheric gases.
Q22. What is the temperature at which a liquid changes into a gas?
Q23. What is the temperature at which a solid changes into a liquid?
Q24. Why are liquids called as fluid?
Q25. The mass per unit volume of a substance is called density. (density = mass/volume). Arrange the following in order of increasing density – air, exhaust from chimneys, honey, water, chalk, cotton and iron.
Q26. Write the full form of LPG and CNG.
Q27. What is boiling point?
Q28. What is melting point?
Q29. Why boiling is considered a bulk phenomenon?
Boiling is a bulk phenomenon. Explain
Q30. How can we change the physical states of matter?
Q31. What are the Five States of Matter?
Q32. Under what conditions heat can be given to a substance without raising its temperature?