Help
Options
Didn't know it?
click below
click below
Knew it?
click below
click below
Don't Know
Remaining cards (0)
Know
retry
shuffle
restart
0:00
Embed Code - If you would like this activity on your web page, copy the script below and paste it into your web page.
Normal Size Small Size show me how
Normal Size Small Size show me how
Chapter 9
Kinetic Theory of Matter and Behaviour of Gases
| Question | Answer |
|---|---|
| What is matter | Matter is anything that takes up space and has mass. |
| What are materials made up of | Materials are made up of small particles is often referred to as the particulate nature of matter. |
| What are the assumptions of the kinetic theory of matter | All matter is made up of tiny particles that are invisible to the naked eye The tiny particles are always in motion. Temperature affects the movement of particles. Temperature can cause a change in state: Solids, Liquids and Gases Forces between particles Pressure in gases |
| How do the tiny particles move in different states of matter | In solids, the particles are packed closely together. They do not have as much energy as particles in the liquid and gas states. The particles can only vibrate about fixed positions, In liquids, the particles are also packed closely together but are not in fixed positions. Evidence for this is the fact that liquids cannot be compressed. In gases, the particles are more widely separated and have larger amounts of energy The energy of gas particles is sufficient to fill a container. |
| How can temperature affect the movement of particles | An increase in temperature causes an increase in the kinetic energy of the particles, i.e. the particles move faster. A decrease in temperature (reduced energy) causes a decrease in the kinetic energy of the particles, i.e. the particles move more slowly. |
| What is it called when a solid turns directly to a gas | This occurrence is known as sublimation. Solid carbon dioxide (‘dry ice’) and iodine are examples of substances that sublime. Dry ice is often used in special effects. |
| What is evaporation | Evaporation is the changing of a liquid to a gas at the surface of the liquid. |
| What is the boiling point of a substance | The boiling point of a liquid is the temperature at which a liquid changes to a gas throughout the liquid. |
| What is condensation | Condensation is the changing of a gas to a liquid (or solid sometimes) |
| What is the freezing point of a substance | The freezing point is the temperature at which a liquid changes to a solid. |
| How do the forces between particles affect them | In solids, the particles are held tightly together by strong forces and this gives solids a definite shape. In liquids, the forces are weaker and these weaker forces allow the particles to slide over each other. Therefore, liquids flow. In gases, the forces are very weak and gases can diffuse to fill all the available space. |
| What are the tiny particles | mainly atoms and molecules. |
| What is a gas | A gas is a substance that has no well-defined boundaries but diffuses rapidly to fill any container in which it is placed. |
| How is there pressure in gases | The Kinetic Theory of Matter explains how gases exert a pressure. This pressure is caused by the gas particles colliding with each other and with the walls of the container. As the temperature is raised, the particles gain more energy and this additional energy increases the pressure. The ability of a gas to diffuse is often used to define what a gas is. |
| what is Brownian Motion | Brownian motion is the random, irregular, zig-zag and continuous movement of tiny particles (such as pollen grains or smoke particles) suspended in a liquid or gas. The movement results from the collisions of these tiny particles with the molecules of the liquid or gas. |
| How is Brownian motion evidence for the theory of kinetic matter | The random, zig-gag, irregular movement of the visible particles (pollen or smoke particles) is observed because they are constantly being bombarded by much smaller, invisible molecules of water or gases in the air. Since Brownian motion is continuously taking place, the smaller molecules must be continuously in motion. |
| What is diffusion | Diffusion is the process by which small particles (atoms, molecules or ions) move from an area of higher concentration to an area of lower concentration. Diffusion can occur in gases, liquids and solids. Note: Diffusion can occur between two solids that are in contact with each other, but the rate of diffusion is usually much slower than in gases and liquids. |
| Does diffusion require external energy to occur | Diffusion is a normal process and does not require any external energy to be applied. It occurs due to the natural kinetic energy of the small particles. |
| How does diffusion provide evidence for the Kinetic Theory of Matter? | The observable evidence of diffusion demonstrates that particles must be in constant motion, colliding with each other and spreading out to occupy all the available space as stated in the assumptions of the Kinetic Theory of Matter. |
| Do gases have a fixed volume | no |
| What does the volume of a gas depend on | the volume of a sample of gas depends on temperature and pressure. |
| What is the volume of a sample gas | The volume of a sample of gas is the same as the volume of the container in which the sample is held. |
| What is the SI of volume | SI unit of volume is the cubic metre (m3). |
| What is 1L in cm3 | 1000cm3 |
| What is another way of saying 1000cm3 | 1 cubic decimetre 1dm3 |
| What two scales of temperature are used in science | the Celsius scale and the Kelvin scale (also called the absolute scale). |
| How many degrees celsius is 0 kelvin (absolute zero) | -273 degrees celcius |
| How can temperature be converted from Celsius to Kelvin | Temperature can be converted from the celsius scale to the kelvin scale by adding 273 to the celsius scale |
| What is the pressure of a gas | The pressure of a gas is the force that the gas exerts on a unit area (e.g. one square metre) of its container. |
| What is the SI unit of pressure | The SI unit of pressure is newtons per metre squared, N m-2. This is also called the pascal (Pa). |
| What is the normal atmospheric pressure | Normal atmospheric pressure is approx. 1 × 103 N m-2 (also written as 1 × 105 Pa or 100 000 Pa). |
| What is the standard temperature | Standard temperature = 273 K (i.e. 0 °C, the freezing point of water) |
| What is the standard pressure | Standard pressure = 1 × 105 Pa or 100 kPa |
| What are the 5 gas laws | Boyles Law Charles Law The combined gas law Gay-Lussac’s Law of combining volumes Avogadro’s law |
| What is Boyles Law | volume is inversely proportional to the pressure. Boyle’s Law states that, at constant temperature, the volume of a fixed mass of gas is inversely proportional to its pressure. pV=k |
| What is Charles Law | volume is directly proportional to temperature on the Kelvin scale. Explanation: If the temperature of the container is increased, the molecules are now moving more quickly due to the extra kinetic energy This means that the molecules collide more frequently and more forcefully with each other and with the walls of the container. In order to prevent an increase in pressure, it is necessary to give the molecules more room in which to move around. Therefore, the volume of the container increases. |
| What is the combined gas law | Combining Boyle’s Law and Charles’ Law, the combined gas Law is obtained: p1,V1/T1 = p2,V2/T2 |
| What is Gay-Lussac's law of combining values | Gay-Lussac’s Law of Combining Volumes states that, in a reaction between gases, the volumes of the reacting gases and the volumes of any gaseous products are in the ratio of small whole numbers, provided the volumes are measured at the same temperature and pressure. |
| What is Avogadro's law | Avogadro’s Law states that equal volumes of gases contain equal numbers of molecules under the same conditions of temperature and pressure. By experiment it is found that a mole of oxygen gas occupies a volume of 22.4 Litres at s.t.p. One mole of any gas contains 6.02 × 1023 molecules, then by Avogadro’s Law, one mole of any gas should occupy 22.4 litres at s.t.p. The volume occupied by one mole of any gas is called its molar volume. Thus, the molar volume of all gases at s.t.p. is 22.4 litres. |
| What are the assumptions of the kinetic theory of matter applied to gases | Gases are made up of particles (molecules or atoms) that are in continuous rapid, random motion, colliding with each other and with the walls of the container. There are no attractive or repulsive forces between the molecules of a gas, i.e. the molecules are independent of each other. The gas molecules are so small and so widely separated that the actual volume of all the molecules is negligible compared with the space they occupy. |
| What are the assumptions of the kinetic theory of matter applied to gases part 2 | When molecules collide, the collisions are perfectly elastic, i.e. there is no loss of kinetic energy in these collisions, although there may be a transfer of energy between the colliding particles. The average kinetic energy of the molecules in a sample of gas is proportional to the temperature measured on the Kelvin scale. |
| What are Limitations to the Kinetic theory of Matter as applied to gases | All real gases actually do have tiny attractive or repulsive forces between the molecules of the gas. Under very high pressure, when molecules are crowded closer together, it is clear that their volume is not negligible compared with the distances between them. |
| What is an ideal gas | An ideal gas is one that perfectly obeys all the assumptions of the kinetic theory of gases under all conditions of temperature and pressure. |
| Is it true to say that all of the assumptions of the kinetic theory do not hold for real gases but only hold for what is called an ideal gas. | Yes |
| Do ideal gases exist | No |
| Under what two conditions do real gases come very close to ideal gas behaviour | At low pressure, when the molecules are widely spaced. At high temperatures, when the molecules are moving rapidly, preventing the forces between molecules from exerting an influence. |
| How do Real gases differ from ideal gases | forces of attraction and repulsion do exist between the molecules. The volume of the molecules is not negligible. |
| What is the Ideal gas equation | Boyle’s Law, Charles’ Law and Avogadro’s Law may be combined to give a mathematical relationship between the volume (V), pressure (p), temperature (T) and number of moles (n) of a gas: pV = nRT |
| What is the Universal Gas Constant (R) | 8.31 J mol-1K-1 |
Created by:
21JulianM
Popular Chemistry sets