📘 Chapter 7: Thermal Properties of Matter – Multiple Choice Questions
Prepared by Muhammad Tayyab, Subject Specialist Physics, Govt Christian High School Daska. Based on PECTAA 2026 syllabus (National Curriculum 2023).
📖 What's Inside: This section covers multiple choice questions from Chapter 7 Thermal Properties of Matter including Kinetic Molecular Theory, Temperature, Heat, Thermometers, Temperature Scales, Absolute Zero, and Thermometric Properties. Each question includes an answer key and detailed explanation as per the official PECTAA 2026 Physics curriculum. Perfect for Punjab Boards (Lahore, Gujranwala, Multan, etc.) and all BISE boards across Pakistan.
📚 Related Resources – Chapter 7: Thermal Properties of Matter
📋 Exercise Short Qs
📝 Short Qs
📖 Comprehensive Qs
🔢 Numerical Problems
✅ MCQs
✏️ Constructed Response
Thermal Properties of Matter covers temperature, heat, thermometers, temperature scales, and kinetic molecular theory.
✅ Multiple Choice Questions & Answer Key (PECTAA 2026)
7.1 How do the molecules in a solid behave?
✅ Correct Answer: (B) Vibrate about their mean positions
In solids, strong intermolecular forces hold molecules at fixed positions, but they still vibrate about their mean positions.
In solids, strong intermolecular forces hold molecules at fixed positions, but they still vibrate about their mean positions.
7.2 What type of motion is of the molecules in a gas?
✅ Correct Answer: (B) Random motion
Gas molecules are relatively far apart and move randomly in all directions.
Gas molecules are relatively far apart and move randomly in all directions.
7.3 Temperature of a substance is:
✅ Correct Answer: (C) degree of hotness or coldness
Temperature is defined as the degree of hotness or coldness of a body.
Temperature is defined as the degree of hotness or coldness of a body.
7.4 Heat is the:
✅ Correct Answer: (D) the energy in transit
Heat is the energy transferred from one object to another due to temperature difference — energy in transit.
Heat is the energy transferred from one object to another due to temperature difference — energy in transit.
7.5 In Kelvin scale, the temperature corresponding to melting point of ice is:
✅ Correct Answer: (D) +273
The melting point of ice is 0°C on Celsius scale, which equals 273 K on Kelvin scale.
The melting point of ice is 0°C on Celsius scale, which equals 273 K on Kelvin scale.
7.6 The temperature which has the same value on Celsius and Fahrenheit scale is:
✅ Correct Answer: (A) -40
At -40°, the Celsius and Fahrenheit scales show the same reading. This can be found by solving \(T = \frac{9}{5}T + 32\).
At -40°, the Celsius and Fahrenheit scales show the same reading. This can be found by solving \(T = \frac{9}{5}T + 32\).
7.7 Which one is a better choice for a liquid-in-glass thermometer?
✅ Correct Answer: (C) Expand linearly
A good thermometric liquid must expand linearly with temperature so that equal temperature changes produce equal scale increments.
A good thermometric liquid must expand linearly with temperature so that equal temperature changes produce equal scale increments.
7.8 One disadvantage of using alcohol in a liquid-in-glass thermometer:
✅ Correct Answer: (C) it wets the glass tube
Alcohol wets the glass tube, which makes reading the thermometer difficult — this is a disadvantage.
Alcohol wets the glass tube, which makes reading the thermometer difficult — this is a disadvantage.
7.9 Water is not used as a thermometric liquid mainly due to:
✅ Correct Answer: (C) non-linear expansion
Water expands unevenly (non-linearly), making it unsuitable for a thermometer scale.
Water expands unevenly (non-linearly), making it unsuitable for a thermometer scale.
7.10 A thermometer has a narrow capillary tube so that it:
✅ Correct Answer: (C) gives a large change for a given temperature rise
A narrow capillary tube amplifies the liquid's expansion, giving a larger scale reading for a small temperature change, increasing sensitivity.
A narrow capillary tube amplifies the liquid's expansion, giving a larger scale reading for a small temperature change, increasing sensitivity.
7.11 Which thermometer is most suitable for recording rapidly varying temperature?
✅ Correct Answer: (A) Thermocouple thermometer
Thermocouple thermometers have very low thermal inertia, so they respond almost instantly to rapidly varying temperatures.
Thermocouple thermometers have very low thermal inertia, so they respond almost instantly to rapidly varying temperatures.
📊 Answer Key Summary
7.1 B
7.2 B
7.3 C
7.4 D
7.5 D
7.6 A
7.7 C
7.8 C
7.9 C
7.10 C
7.11 A
📐 Key Concepts – Thermal Properties of Matter (MCQs)
Temperature: Degree of hotness or coldness
Heat: Energy in transit due to temperature difference
Absolute Zero: 0 K = -273.15°C
Temperature Scales: Celsius, Fahrenheit, Kelvin
Thermometric Liquid: Mercury (linear expansion, visible)
💡 Exam Tip:
For multiple choice questions, read each option carefully. Pay attention to key concepts like Kinetic Molecular Theory, temperature vs heat, thermometric properties, temperature scales, and thermometer types. These questions follow the PECTAA 2026 pattern and are prepared by Subject Specialist Muhammad Tayyab.
Chapter 1Physical Quantities and Measurements
Chapter 2Kinematics
Chapter 3Dynamics
Chapter 4Turning Effect of Forces
Chapter 5Work and Energy
Chapter 6Mechanical Properties of Matter
Chapter 7✨ Thermal Properties of Matter
Chapter 8Magnetism
Chapter 9Nature of Science
📖 Complete syllabus coverage for Class 9 Physics (PECTAA 2026) – Chapters 1 to 9
Created by Hira Science Academy | Aligned with PECTAA 2026 Syllabus