The question asks for the specific term used to describe the phase transition when ice (solid state) changes into water (liquid state). This involves understanding the basic terminology of phase changes in matter.
B) Fusion
Fusion is the scientific term for the process of melting, where a substance changes from a solid to a liquid state due to the absorption of heat energy. When ice melts into water, it absorbs latent heat of fusion, causing its molecules to gain enough kinetic energy to overcome the rigid structure of the solid state and move more freely as a liquid.
The question asks for the general term describing the phase transition from a liquid state to a gaseous state. We need to evaluate each option based on its scientific definition in the context of phase changes.
C) Vaporization — This is the overarching term for the phase transition where a substance changes from a liquid to a gas. It includes both evaporation and boiling.
The question asks for the definition of the heat of fusion. This is a fundamental concept in thermodynamics and phase transitions. We need to identify the option that correctly defines this specific latent heat.
A) Heat required to melt 1 gram of a solid
This option accurately describes the heat of fusion. The heat of fusion is the amount of heat energy needed to convert a unit mass of a solid into a liquid at its melting point, without a change in temperature. For example, the latent heat of fusion of ice is approximately \(334 \, \text{J/g}\) or \(80 \, \text{cal/g}\).
This question tests basic understanding of the kinetic theory of matter, specifically how temperature affects molecular motion in liquids. When a substance is heated, it gains thermal energy, which is converted into kinetic energy of its constituent molecules.
A) Faster — When a liquid is heated, its molecules absorb thermal energy, which increases their kinetic energy. Higher kinetic energy means the molecules move at a greater speed, hence they move faster.
The total heat energy contained within an object, often referred to as its internal energy or thermal energy, depends on several factors. We need to identify the primary physical properties that directly influence this energy.
Correct Option: B) Mass and temperature. The total heat energy in an object is directly proportional to its mass and its temperature (assuming specific heat capacity is constant for the material). More mass means more particles to hold energy, and higher temperature means each particle has more kinetic energy.
The question asks about the mode of heat transfer that can occur through a vacuum. We need to recall the definitions and requirements for each primary mode of heat transfer: conduction, convection, and radiation.
Correct Option: A) Radiation — Radiation is the transfer of heat in the form of electromagnetic waves. These waves do not require any material medium for their propagation and can travel through a vacuum. This is how heat from the Sun reaches the Earth, travelling through the vacuum of space.