Search results
May 20, 2018 · A solid has definite volume and shape, a liquid has a definite volume but no definite shape, and a gas has neither a definite volume nor shape. Figure \(\PageIndex{2}\): A Representation of the Solid, Liquid, and Gas States. (a) Solid O 2 has a fixed volume and shape, and the
- What is Matter
Air (and all other gases) are invisible to the eye, have...
- Chapter 13: Solutions
Words such as dilute or concentrated are used to describe...
- 7.11: The Activity Series
However, we have a tool that allows us to make better...
- 3.2: Physical States of Matter
A solid has definite volume and shape, a liquid has a...
- What is Matter
The state that water is in depends upon the temperature, each state has its own unique set of physical properties. Matter typically exists in one of three states: solid, liquid, or gas. Figure 1.4.1 1.4. 1: Matter is usually classified into three classical states. From left to right: quartz (solid), water (liquid), nitrogen dioxide (gas).
- Overview
- Structure
- Kinetic-molecular picture
- Numerical magnitudes
gas, one of the three fundamental states of matter, with distinctly different properties from the liquid and solid states.
The remarkable feature of gases is that they appear to have no structure at all. They have neither a definite size nor shape, whereas ordinary solids have both a definite size and a definite shape, and liquids have a definite size, or volume, even though they adapt their shape to that of the container in which they are placed. Gases will completely...
Gases nevertheless do have a structure of sorts on a molecular scale. They consist of a vast number of molecules moving chaotically in all directions and colliding with one another and with the walls of their container. Beyond this, there is no structure—the molecules are distributed essentially randomly in space, traveling in arbitrary directions at speeds that are distributed randomly about an average determined by the gas temperature. The pressure exerted by a gas is the result of the innumerable impacts of the molecules on the container walls and appears steady to human senses because so many collisions occur each second on all sections of the walls. More subtle properties such as heat conductivity, viscosity (resistance to flow), and diffusion are attributed to the molecules themselves carrying the mechanical quantities of energy, momentum, and mass, respectively. These are called transport properties, and the rate of transport is dominated by the collisions between molecules, which force their trajectories into tortuous shapes. The molecular collisions are in turn controlled by the forces between the molecules and are described by the laws of mechanics.
Thus, gases are treated as a large collection of tiny particles subject to the laws of physics. Their properties are attributed primarily to the motion of the molecules and can be explained by the kinetic theory of gases. It is not obvious that this should be the case, and for many years a static picture of gases was instead espoused, in which the pressure, for instance, was attributed to repulsive forces between essentially stationary particles pushing on the container walls. How the kinetic-molecular picture finally came to be universally accepted is a fascinating piece of scientific history and is discussed briefly below in the section Kinetic theory of gases. Any theory of gas behaviour based on this kinetic model must also be a statistical one because of the enormous numbers of particles involved. The kinetic theory of gases is now a classical part of statistical physics and is indeed a sort of miniature display case for many of the fundamental concepts and methods of science. Such important modern concepts as distribution functions, cross sections, microscopic reversibility, and time-reversal invariance have their historical roots in kinetic theory, as does the entire atomistic view of matter.
Britannica Quiz
So Much Chemistry, So Little Time Quiz
When considering various physical phenomena, it is helpful for one to have some idea of the numerical magnitudes involved. In particular, there are several characteristics whose values should be known, at least within an order of magnitude (a factor of 10), in order for one to obtain a clear idea of the nature of gaseous molecules. These features i...
- Edward A. Mason
Sep 18, 2023 · A solid has definite volume and shape, a liquid has a definite volume but no definite shape, and a gas has neither a definite volume nor shape. Figure \(\PageIndex{2}\): A representation of the solid, liquid, and gas states. (a) Solid O 2 has a fixed volume and shape, and the
Feb 16, 2022 · Gas is a state of matter that has no fixed shape and no fixed volume. Gases have a lower density than other states of matter, such as solids and liquids. There is a great deal of empty space ...
Jun 7, 2024 · The four main states of matter are solids, liquids, gases, and plasma. Under exceptional conditions, other states of matter also exist. A solid has a definite shape and volume. A liquid has a definite volume, but takes the shape of its container. A gas lacks either a defined shape or volume.
People also ask
What are the differences between solids liquids and gases?
Do gases have a definite shape?
Why does a liquid have a definite volume?
Does a solid have a definite volume and shape?
Which state of matter has a definite shape and volume?
Does a change from liquid to gas change the volume?
Jan 28, 2020 · The formal physics description of a gas is a substance that does not have a definite volume (also called a fixed volume) or a definite shape. Instead, a gas will take the shape of its container because gas molecules can move freely past one another.
