Pearson Edexcel International GCSE (9–1) · PHYSICS · Unit
Solids, Liquids and Gases
279 practice questions
Topics covered
Practice questions
131–140 of 144 · Normal
Question 131
1 mark · Normal
Answer and check →Which temperature is closest to absolute zero?
- A.0 °C
- B.-273 °C
- C.273 K
- D.100 K
Question 132
3 marks · Normal
Answer and see the solution →A physics classroom is at 18 °C. A scientist is cooling a gas sample to investigate pressure at lower temperatures.
(a)[1 mark]Convert the classroom temperature to kelvin.
(b)[1 mark]The gas is cooled to 5 °C. What is this temperature in kelvin?
(c)[1 mark]If the gas were cooled to 0 K, what would happen to the motion of the particles? Explain.
Question 133
2 marks · Normal
Answer and see the solution →Why must you convert temperatures to kelvin before using gas law equations?
Question 134
1 mark · Normal
Answer and see the solution →A student writes this formula for converting celsius to kelvin:
T_kelvin = T_celsius + 273Question 135
5 marks · Normal
Answer and see the solution →A student places a glass bottle full of air with a tight lid in a refrigerator. The air inside was initially at room temperature (22 °C) and atmospheric pressure (100 kPa). After several hours, the bottle’s temperature has dropped to 4 °C.
(a)[2 marks]Explain, using the idea of gas particles, what happens to the pressure of the air in the bottle as it cools.
(b)[3 marks]Calculate the final pressure of the air in the bottle, in kPa. Give your answer to 2 significant figures. (You must use the Kelvin scale for temperature.)
Question 136
5 marks · Normal
Answer and see the solution →A fixed mass of gas in a metal cylinder is at a pressure of 120 kPa and a temperature of 300 K. The gas is then compressed while being heated, so that its temperature rises to 360 K and its volume halves.
(a)[1 mark]Write down the gas law equation that links pressure, volume, and temperature for a fixed mass of gas.
(b)[3 marks]Calculate the final pressure of the gas, in kPa.
(c)[1 mark]Explain why the pressure in the cylinder increases, even though the gas is heated.
Question 137
5 marks · Normal
Answer and see the solution →A balloon filled with helium has a pressure of 105 kPa and a volume of 1.8 litres at 25°C. The balloon is taken outside where the temperature drops to 5°C, but the pressure remains constant.
(a)[2 marks]Explain what happens to the average kinetic energy of the helium molecules as the temperature changes. Your answer should refer to the temperature in Kelvin.
(b)[3 marks]Calculate the new volume of the balloon at 5°C. Give your answer to 2 significant figures.
Question 138
5 marks · Normal
Answer and see the solution →The graph below shows how the pressure of a fixed mass of gas at constant volume varies with temperature:
Graph of pressure vs. temperature (°C) for a fixed volume of gas (a)[2 marks]Determine the temperature at which the pressure of the gas would reach zero according to the graph.
(b)[3 marks]Explain what this value represents physically, and how it is linked to the kinetic energy of the gas molecules.
Question 139
6 marks · Normal
Answer and see the solution →A science teacher uses an ice block and an iron block to demonstrate differences in properties of solids and liquids. She measures the volume and mass of both blocks. Later, she places the iron block on a wooden bench and the ice block in water.
(a)[2 marks]State the equation to calculate the density of a substance, and name the correct SI unit for density.
(b)[2 marks]The iron block has a mass of 1.20 kg and a volume of 1.5 × 10⁻⁴ m³. Calculate the density of the iron block.
(c)[2 marks]When the iron block is placed on a wooden bench, it exerts a force of 12 N over an area of 0.006 m². Calculate the pressure applied to the bench by the iron block. Give your answer in Pa.
Question 140
5 marks · Normal
Answer and see the solution →A student observes the boiling of water and describes the random motion of bubbles inside it.
(a)[2 marks]Explain how the random motion of water molecules results in boiling and formation of bubbles.
(b)[2 marks]Describe, in terms of pressure, what happens to the bubbles as they rise towards the surface.
(c)[1 mark]State the property of pressure in liquids that explains why bubbles are spherical.