Physical Changes in Matter
42 Questions
4 Views

Choose a study mode

Play Quiz
Study Flashcards
Spaced Repetition
Chat to lesson

Podcast

Play an AI-generated podcast conversation about this lesson

Questions and Answers

What happens to the water molecules when a gas cools down and condenses into a liquid?

  • They lose kinetic energy. (correct)
  • They remain unchanged.
  • They gain kinetic energy.
  • They transform into a solid.

    • Which of the following substances vaporises easily at room temperature?

  • Cooking oil
  • Ice
  • Dry ice
  • Petrol (correct)

    • What is the process called when a solid changes directly into a gas?

  • Melting
  • Sublimation (correct)
  • Vaporization
  • Condensation

    • What is the term for the process when a liquid is heated to its boiling point?

    <p>Vaporization</p> Signup and view all the answers

    What characterizes a physical change?

    <p>The change can be undone</p> Signup and view all the answers

    Which of the following statements correctly describes freezing?

    <p>It's the solidification of a liquid.</p> Signup and view all the answers

    What is the term for the gas form of a substance that is typically solid or liquid at room temperature?

    <p>Vapor</p> Signup and view all the answers

    Which phenomenon occurs when water vapor condenses on a cold surface?

    <p>Condensation</p> Signup and view all the answers

    What happens to water molecules when ice melts?

    <p>They vibrate faster and break free from the lattice</p> Signup and view all the answers

    What result can be observed when dry ice warms up?

    <p>It sublimates into carbon dioxide gas.</p> Signup and view all the answers

    Which statement about sublimation is true?

    <p>It is the transition from solid directly to gas</p> Signup and view all the answers

    In the context of states of matter, which process is directly opposite to vaporization?

    <p>Condensation</p> Signup and view all the answers

    What term describes a substance that easily becomes a gas at normal temperature?

    <p>Volatile</p> Signup and view all the answers

    What occurs when heat energy is added to solid water (ice)?

    <p>The molecules vibrate faster and may turn to liquid</p> Signup and view all the answers

    In the context of physical changes, what is a lattice?

    <p>A three-dimensional arrangement of particles</p> Signup and view all the answers

    How does the density of ice compare to liquid water?

    <p>Ice has lower density than water</p> Signup and view all the answers

    What is the smallest unit of an element that retains the properties of that element?

    <p>Atom</p> Signup and view all the answers

    Which of the following terms refers to a substance that is made up of two atoms of the same element?

    <p>Diatomic molecule</p> Signup and view all the answers

    Which of the following elements is a noble gas?

    <p>Argon</p> Signup and view all the answers

    The horizontal rows in the periodic table are called:

    <p>Periods</p> Signup and view all the answers

    What is the main function of chlorophyll in plants?

    <p>Photosynthesis</p> Signup and view all the answers

    Which structure in the plant is responsible for transporting water and nutrients from the roots to the rest of the plant?

    <p>Xylem</p> Signup and view all the answers

    Which of the following is a symptom of asthma?

    <p>Coughing</p> Signup and view all the answers

    What is the main function of the respiratory system?

    <p>Facilitating gas exchange</p> Signup and view all the answers

    A physical change occurs when the molecules of a substance remain the same, but the substance has different properties.

    <p>True</p> Signup and view all the answers

    A change in the state of matter (solid, liquid, or gas) is a physical change.

    <p>True</p> Signup and view all the answers

    Physical changes are always irreversible.

    <p>False</p> Signup and view all the answers

    The temperature at which a liquid boils and becomes a gas is called the boiling point.

    <p>True</p> Signup and view all the answers

    Sublimation is a change of state from a liquid to a gas.

    <p>False</p> Signup and view all the answers

    A physical change involves a change in the composition of the substance.

    <p>False</p> Signup and view all the answers

    Melting is an example of a physical change.

    <p>True</p> Signup and view all the answers

    A change in state (solid, liquid, or gas) is always a chemical change.

    <p>False</p> Signup and view all the answers

    A three-dimensional arrangement of particles in a regular pattern is called a crystal.

    <p>False</p> Signup and view all the answers

    Sublimation is a change of state from a solid directly to a gas, skipping the liquid state.

    <p>True</p> Signup and view all the answers

    Condensation is a change of state from a gas to a liquid.

    <p>True</p> Signup and view all the answers

    Freezing is a change of state from a liquid to a solid.

    <p>True</p> Signup and view all the answers

    A volatile substance easily becomes a gas at temperatures below its boiling point.

    <p>True</p> Signup and view all the answers

    The process of changing from a gas to a solid is called deposition.

    <p>True</p> Signup and view all the answers

    Explain why physical changes are often reversible.

    <p>Physical changes are reversible because they only alter the arrangement or appearance of the substance, not its chemical composition. The molecules of the substance remain unchanged during a physical change, so the original substance can be recovered by reversing the change.</p> Signup and view all the answers

    Give an example of a physical change. Explain how it fits the definition of a physical change.

    <p>A common example is melting ice into water. This is considered a physical change because the molecules of water remain the same (H2O). The change only affects the state of water, from solid ice to liquid water. This change is reversible by freezing the liquid water back into ice.</p> Signup and view all the answers

    What is the difference between a liquid and a gas? Explain how the arrangement of their molecules contributes to this difference.

    <p>The main difference between a liquid and a gas lies in the arrangement and movement of their molecules. In a liquid, the molecules are closer together and can move around more freely than in a solid. However, the molecules in a gas are much farther apart and move more independently, bouncing off each other and expanding to fill their container. Liquids have a definite volume but take the shape of their container, while gases have no fixed volume or shape. This difference in their molecular arrangement and movement is what gives liquids and gases their unique properties.</p> Signup and view all the answers

    What is the difference between evaporation and boiling?

    <p>Evaporation is a slow process where a liquid changes into a gas at temperatures below its boiling point. It occurs at the surface of the liquid as some molecules gain enough energy to break free and disperse as a gas. Boiling, on the other hand, is a rapid process where a liquid changes into a gas at its boiling point. It occurs throughout the whole liquid as more molecules have enough energy to overcome the intermolecular forces holding them together. Boiling occurs at a specific temperature, while evaporation occurs at a range of temperatures.</p> Signup and view all the answers

    Study Notes

    Physical Changes

    • A physical change alters the shape or appearance, but not the substance's makeup.
    • During a physical change, the molecules of the substance remain the same.
    • Changes in state (solid, liquid, gas) are physical changes.
    • Physical changes are typically reversible.

    Key Points

    • Lattice: A three-dimensional arrangement of particles in a regular pattern.
    • Vaporisation/Evaporation: Changing from a liquid to a gas.
    • Vapour: The gaseous form of a substance usually a solid or liquid at room temperature (e.g., water vapor).
    • Volatile: A substance that easily changes to a gas at room temperature.
    • Boiling Point (BP): The temperature at which a liquid boils and becomes a gas.
    • Condensation: Changing from a gas to a liquid.
    • Sublimation: Changing directly from a solid to a gas.
    • Melting: Changing from a solid to a liquid.

    Reversability of Physical Changes

    • Physical changes can be reversed.
    • For example, freezing water into ice, which can be melted back into water.
    • The molecules remain the same; only the arrangement and energy of the molecules change.
    • In ice, water molecules are in a fixed three-dimensional arrangement (lattice), while in liquid water, they have more freedom to move.

    Changing State

    • Substances can change between solid, liquid, and gaseous states.
    • The change of state depends on temperature.
    • Increased temperatures generally cause substances to change from solid to liquid to gas, while decreasing temperatures do the opposite.
    • Examples include melting ice, boiling water, and dry ice subliming.

    Vaporisation and Condensation

    • Vaporisation is the process of a liquid becoming a gas.
    • Vapors are gases formed from substances that are normally solid or liquid at room temperature.
    • Condensation is the process of a gas becoming a liquid.
    • The kinetic energy of molecules in a gas determines if it changes state and the process.

    Melting and Solidification

    • Melting is the changing of a solid into a liquid through increasing temperature.
    • Solidification is the changing of a liquid into a solid through decreasing temperature.
    • The molecules don't change during melting or solidification, only their energy and arrangement.

    Sublimation

    • Some substances can change directly from a solid to a gas or from a gas to a solid, without passing through the liquid phase.
    • This is called sublimation.
    • Dry ice (solid carbon dioxide) is a common example of sublimation.

    Studying That Suits You

    Use AI to generate personalized quizzes and flashcards to suit your learning preferences.

    Quiz Team

    Related Documents

    Physical and Chemical Changes PDF
    Year 8 Semester 2 Practice Exam PDF

    Description

    This quiz covers the concept of physical changes in matter, including their characteristics and examples such as melting and evaporation. Understand the processes involved and the reversibility of these changes. Test your knowledge on key terms and definitions related to physical transformations.

    More Like This

    Use Quizgecko on...
    Browser
    Open
    Browser
    Browser