States Of Matter Test (23/02/2026)

 

CHEMISTRY TEST – States Of Matter 

Total Marks: 50. Time: 1 hour

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Section A: Multiple Choice Questions (5 marks)

Choose the correct answer.

1. The unit of viscosity in CGS system is:
   1. Newton
   2. Dyne
   3. Poise
   4. Pascal
2. For 2 moles of an ideal gas, the ideal gas equation becomes:
   1. PV = RT
   2. PV = 2RT
   3. PV = nRT
   4. PV = T
3. At constant temperature, pressure of a gas is inversely proportional to its volume. This law is:
   1. Charles’ Law
   2. Boyle’s Law
   3. Avogadro’s Law
   4. Dalton’s Law
4. The intermolecular forces in liquids are:
   1. Greater than solids
   2. Less than gases
   3. Greater than gases but less than solids
   4. Equal to gases
5. Density of a gas at constant temperature and pressure is directly proportional to its:
   1. Volume
   2. Molar mass
   3. Temperature
   4. Pressure

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Section B: Very Short Answer Questions (Any 5) (10 marks)

1. Define partial pressure.
2. State Charles’ Law.
3. What happens to the size of a methane bubble as it rises from deep sea to surface?
4. Name the intermolecular force present in CH₃OH.
5. Convert −100°C into Kelvin.
6. Why are intermolecular forces assumed negligible in an ideal gas?
7. What is vapour pressure?

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Section C: Long Answer Questions (Any 5) (25 marks)

1. Derive the Ideal Gas Equation. Mention the terms involved.
2. State and explain Dalton’s Law of Partial Pressures with an example.
3. Identify and explain the gas law applicable in each case:
   1. Pressure increases when volume decreases at constant temperature.
   2. Volume increases with temperature at constant pressure.
   3. Volume is directly proportional to number of moles at constant T and P.
4. Differentiate between Real Gas and Ideal Gas (any four points).
5. Explain why hot air balloons rise using a suitable gas law.
6. Write the postulates of Kinetic Theory of Gases (any five).
7. Define and explain:
   1. Surface tension
   2. Viscosity
   3. Hydrogen bonding

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Section D: Numerical Problems (Any 5) (10 marks)

1. A gas occupies 2.0 L at 1 atm. What will be its volume at 2 atm at constant temperature?
2. A gas at 27°C occupies 3.0 L. What will be its volume at 127°C at constant pressure?
3. Calculate the pressure exerted by 1 mole of gas in a 22.4 L container at 273 K. (R = 0.0821 L atm mol⁻¹ K⁻¹)
4. Convert 1.5 atm into Pascals. (1 atm = 1.013 × 10⁵ Pa)
5. Calculate the number of moles present in 4.48 L of gas at STP.
6. A gas has density 2 g/L at STP. Calculate its molar mass.
7. 600 mL of gas at 25°C and 760 mm Hg is changed to 10°C and 640 mL. Calculate the new pressure.

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End of Question Paper