Test: Matter And Its Composition - Class 9 MCQ

The law of conservation of mass states that mass cannot be created or destroyed in a chemical reaction. Thus, the total mass of the reactants before a reaction equals the total mass of the products after the reaction.

Solids have a fixed shape and fixed volume due to the strong forces of attraction between closely packed particles, which maintain their structure even under external forces.

Increasing wind speed enhances evaporation by removing vapor from the surface of the liquid, allowing more molecules to escape into the air. Other factors like temperature and surface area also play important roles.

Plasma is a highly ionized state of matter containing equal numbers of positive and negative charges, with particles in a super energetic state. This makes it distinct from solids, liquids, and gases.

Gases can be easily compressed because the particles are far apart and have negligible forces of attraction between them. This allows gas particles to be squished into a smaller volume.

Freezing, also known as solidification, is the process where a liquid loses heat and changes into a solid at a specific temperature called the freezing point. This transition occurs as particles lose kinetic energy and arrange themselves into a fixed structure.

In liquids, particles are not fixed in place and can slip and slide over each other, leading to a lack of definite shape while maintaining a fixed volume. This allows liquids to take the shape of their container.

Evaporation is the process where a liquid changes into a gas at temperatures below its boiling point, occurring primarily at the surface of the liquid. This is influenced by factors like temperature and surface area.

Sublimation is the process in which a substance changes directly from a solid to a gas without passing through the liquid state. Common examples include dry ice and iodine.

Melting occurs when a solid absorbs heat, causing its particles to gain energy and break free from their fixed positions, transforming the solid into a liquid at a specific temperature known as the melting point.

The Bose–Einstein Condensate is formed at extremely low temperatures, where particles occupy the same quantum state, resulting in unique properties that differ from other states of matter.

Brownian motion refers to the random motion of particles suspended in a fluid, which results from their bombardment by fast-moving atoms or molecules in the fluid. This phenomenon illustrates the kinetic energy of particles.

The boiling point of a liquid is the temperature at which it changes from liquid to gas throughout the entire liquid, not just at the surface. This process can occur at various temperatures depending on pressure.

The latent heat of fusion is the amount of heat energy required to convert 1 kilogram of solid into liquid at its melting point. This energy is necessary to overcome the forces holding the particles in a solid state.

Matter is defined as anything that occupies space or volume, has mass, and can be perceived by our senses. This broad definition includes all materials, whether solid, liquid, or gas.