Solids, liquids and gases Transitional Reasoning Practice

Questions

1. 1.

   A sealed syringe containing a fixed mass of gas at constant temperature is compressed, reducing the volume occupied by the gas to half of its initial value. An attached digital sensor records that the pressure exerted by the gas on the syringe walls doubles. Based on the particle model of matter, which statement correctly explains this increase in pressure?

   • A) The gas particles absorb energy from the compression, increasing their average speed and striking the walls with greater individual force.
   • B) The gas particles are squeezed together, causing the individual particles to expand and exert a greater contact force on the walls.
   • C) The repulsive forces between neighboring gas particles strengthen significantly, driving them continuously outward into the walls.
   • D) The gas particles maintain the same average speed, but the smaller volume causes them to collide with the walls more frequently per unit area.
2. 2.

   A sealed rigid chamber of fixed volume is completely filled with a single substance. A valve extracts exactly half of the substance's mass under constant temperature, after which the chamber is resealed. Monitoring sensors record that the remaining substance redistributes uniformly throughout the entire volume of the chamber, resulting in a uniform 50% decrease in density throughout the interior space. Based on the particle model of matter, which deduction correctly explains this behavior?

   • A) The substance is a liquid because attractive forces between particles draw them apart into the newly vacated region of the vessel.
   • B) The substance is a solid because the extraction of mass relieves internal pressure, causing individual particles to expand in size.
   • C) The substance is a gas because negligible attractive forces allow its rapidly moving particles to disperse until they occupy all available space.
   • D) The substance is a liquid because particles that slide past one another naturally spread apart to maintain an even distribution throughout any closed container.
3. 3.

   A student applies a steady sideways force to the upper surface of a solid block, causing the block to tilt slightly and resist further deformation. When the student applies the same sideways force to the surface of a liquid, the liquid deforms continuously and flows rather than maintaining a stable shape. Based on the particle model of matter, which explanation best accounts for why the solid resists continuous deformation while the liquid flows?

   • A) Solid particles are held in fixed relative positions by strong attractive forces that resist lateral displacement, whereas liquid particles are free to slide past one another because their attractive forces do not lock them into a rigid arrangement.
   • B) Solid particles are completely stationary with zero kinetic energy, whereas liquid particles possess enough energy to eliminate all attractive forces between them.
   • C) Solid particles have greater individual mass than liquid particles, which generates strong gravitational attraction that prevents sideways motion.
   • D) Solid particles have no empty space between them, whereas liquid particles are separated by large gaps of empty space that allow continuous expansion.
4. 4.

   Pressure sensors are installed on the top, bottom, and side walls of identical sealed chambers containing equal masses of a solid, a liquid, and a gas. Measurements reveal that the solid exerts force only on the bottom floor, the liquid exerts pressure on the floor and submerged side walls, while the gas exerts an equal, steady pressure across all interior walls, including the ceiling. Based on the particle model of matter, which statement best explains why the gas exerts pressure on the top surface of its container?

   • A) Gas particles are naturally buoyant against gravity, causing them to float upward and rest continuously against the ceiling.
   • B) Gas particles vibrate within an expanding lattice that pushes outward until it makes physical contact with the ceiling.
   • C) Strong attractive forces between gas particles pull them toward the chamber boundaries, wedging them against the ceiling.
   • D) Gas particles have negligible intermolecular attractions and move rapidly in all directions, continually colliding with the ceiling.
5. 5.

   A student investigates how matter responds to heating by warming equal initial volumes of a solid metal bar, a liquid oil, and an enclosed gas by 20 °C under constant atmospheric pressure. The student observes that the gas undergoes a large increase in volume, the liquid exhibits a very small expansion, and the solid shows an almost imperceptible change in dimensions. Based on the particle model of matter, which explanation best accounts for why the gas expands much more than the liquid and solid under the same temperature increase?

   • A) Individual gas particles expand in volume upon heating, whereas solid and liquid particles remain rigid and fixed in size.
   • B) Gas particles absorb significantly more kinetic energy per degree Celsius than particles in solids and liquids.
   • C) Gas particles experience negligible attractive forces and can move farther apart as their speed rises, whereas strong cohesive forces keep solid and liquid particles bound close together.
   • D) Particles in solids and liquids are completely stationary and unable to alter their spacing, whereas gas particles only begin moving once thermal energy is added.
6. 6.

   A student places equal amounts of a crystalline solid, a liquid, and an unsealed gas into separate open containers at room temperature. The student observes that the solid particles remain in a stable pile without leveling out, the liquid flows to form a flat horizontal upper surface within the container, and the gas spreads outward into the surrounding room without forming any boundary. Based on the particle model of matter, which statement correctly accounts for these different behaviors?

   • A) Solid particles maintain their piled arrangement because they possess no kinetic energy, whereas liquid particles expand continuously to fill all available space.
   • B) Liquid particles form a level surface because strong mutual repulsion forces them apart until they reach the walls, whereas gas particles are driven upward solely by buoyant forces.
   • C) Gas particles escape because the transition to the gaseous state breaks individual molecules into separate atoms, whereas liquid particles remain locked in a flexible lattice.
   • D) Liquid particles can slide past one another while remaining held together by cohesive forces to settle under gravity, whereas solid particles are held in fixed relative positions and gas particles move independently in all directions.
7. 7.

   A researcher suspends microscopic fluorescent beads into three transparent media representing a solid, a liquid, and a gas to observe their behavior under a microscope. In the solid medium, the beads remain permanently locked at fixed positions; in the liquid, they wander along continuous, erratic paths; and in the gas, they undergo rapid, sharp displacements across greater distances between direction changes. Based on the particle model of matter, which conclusion correctly explains the physical cause of these differing behaviors?

   • A) Particles in the solid possess zero kinetic energy and remain completely stationary, while particles in the gas experience strong mutual repulsions that push the beads outward.
   • B) Particles in the solid are bound in fixed positions and can only vibrate in place, whereas particles in the liquid and gas possess translational freedom to collide randomly with the beads.
   • C) Particles in the liquid travel with greater average speeds than particles in the gas, producing heavier impacts that prevent the beads from traversing larger open distances.
   • D) Particles in the gas expand in physical volume upon collision, exerting continuous contact pressure that propels the beads across the empty spaces.
8. 8.

   A student measures the time required for a mechanical vibration to travel through identical 1.0-meter columns containing a solid, a liquid, and a gas at room temperature. The recorded data shows that the vibration reaches the detector fastest in the solid, takes moderately longer in the liquid, and takes the longest time in the gas. Based on the particle model of matter, which explanation best accounts for this observed difference?

   • A) Particles in solids are tightly packed and held by strong attractive forces, enabling vibrational energy to transfer rapidly to adjacent particles, whereas gas particles are widely separated and rely on random collisions across empty space.
   • B) Particles in gases have higher average speeds, which causes the mechanical pulse to scatter randomly in all directions rather than moving forward through the column.
   • C) Particles in liquids and gases absorb the mechanical pulse by compressing their individual particle volumes, whereas solid particles cannot undergo compression.
   • D) Particles in solids travel directly along the entire length of the rod to deliver the pulse, whereas particles in liquids and gases stay in fixed positions.
9. 9.

   An investigator introduces a tiny droplet of colored liquid into a beaker of undisturbed water and simultaneously releases an equal volume of colored gas into a sealed, transparent chamber of undisturbed air at the same temperature. Within seconds, the colored gas disperses uniformly throughout the entire chamber, whereas the colored liquid in the water forms a localized plume that takes several hours to distribute evenly without stirring. Based on the particle model of matter, which statement correctly explains this difference in spreading rates?

   • A) Gas particles exert strong repulsive forces that actively push them apart, whereas liquid particles experience no intermolecular forces.
   • B) Gas particles possess a much lower average kinetic energy than liquid particles, enabling them to slip past air particles without resistance.
   • C) Gas particles move rapidly through large empty spaces between air particles, whereas liquid particles are closely packed and repeatedly collide with neighboring water particles.
   • D) Gas particles have a fundamentally smaller mass and diameter than liquid particles, allowing them to filter directly through the structure of air.
10. 10.

    A sealed container contains a fixed mass of a pure substance. When thermal energy is added, the substance expands to fill the entire container, increasing its volume by more than a thousand times while maintaining the same mass, and its particles transition from sliding past one another to moving rapidly and independently in all directions. Based on the particle model of matter, which deduction correctly explains this transition?

    • A) The substance melted from a solid to a liquid, causing individual particles to expand in size while maintaining fixed positions.
    • B) The substance evaporated from a liquid to a gas, overcoming attractive forces so that the average separation between particles increased drastically.
    • C) The substance sublimed directly from a solid to a gas, meaning the particles lost their kinetic energy and became less dense.
    • D) The substance condensed from a gas to a liquid, allowing stronger attractive forces to push the particles farther apart.
11. 11.

    A student investigates the microscopic basis of compressibility by applying an identical downward force to the pistons of three sealed, identical syringes containing equal volumes of sand, water, and air. The student observes that the volume occupied by air decreases substantially under moderate force, whereas the volumes of sand and water show no measurable decrease. Which deduction correctly explains this observed difference based on the particle model of matter?

    • A) Sand and water particles deform internally to absorb the applied force, whereas air particles remain rigid and bounce elastically.
    • B) Stronger intermolecular attractive forces pull gas particles together under pressure, whereas solid and liquid particles exhibit permanent electrostatic repulsion.
    • C) Particles in liquids and solids possess greater average kinetic energy, which actively pushes the piston upward against external pressure.
    • D) The empty space separating gas particles is vastly larger than the particles themselves, whereas particles in solids and liquids are already closely packed.
12. 12.

    A student investigates three unidentified substances, designated as P, Q, and R, at room temperature. Sample P maintains its distinct shape and volume when transferred into differently shaped open dishes. Sample Q changes its shape to match the base of any container it is poured into while retaining a constant volume, resisting noticeable compression. Sample R completely expands to fill any sealed container into which it is introduced, and its volume decreases significantly when moderate external pressure is applied. Based on these observations, which statement correctly identifies one of the substances and its underlying particle behavior?

    • A) Sample P is a liquid because its particles are arranged in rigid, fixed positions that prevent it from flowing.
    • B) Sample Q is a gas because its particles are separated by large distances, allowing it to adapt to the container shape.
    • C) Sample R is a gas because it expands to fill any available volume and its widely spaced particles allow easy compression.
    • D) Sample Q is a solid because its fixed volume prevents its particles from moving relative to each other.

Answers and step-by-step solutions appear after you finish the test.