chemistry
valatile
a liquid that evaportates at room temp
evaporatio
the process at which a liquid turnsto a gas below its boiling point
liquid to solid aragement/movement
cool liquid until it freezes, particles lose kinetic energy, when temp is low enough the particles no longer have energy to slide. The forces of attraction can hold the particles together in a regular pattern.
solid to lique movement / arangment
heat the solid until it begins to melt. The particles gain kinetic energy an begin to vibrate fast. When the temp is high enough the vibration is sufficient enought to break the forces of attraction. The break from their regular shape. They slide past each other
liquid to gas movement/arangement
heat the lique until it boils. The partciles gain more kinetic energy and move further apart. The attrack of forces in the liquid are broken. Bubbles of gas particles escape from the liquid. The substance becomes a gas.
gas to liquid
cool the gas until it condenses, when the gas is cooled, the particles lose kinetic energy. and the forces of attraction are great enough to keep the particles close together.
solid to gas movement/arangement
heat the solid until it sublimes, the solid particles gain kinetic energy and vibrate faster. The forces of attraction are completely broken and they escape from the solid as a gas.
browmian motion
the random movemnt of particles in a fluid due to their collision with other atoms or molecules
diffusion
is the spreading out of particles at a higher concentration to where they are at a lower concentration.(there are a fewer of them in a certain volume)
diffusion of gas
split a jar of bromine gas and air with a glass plate. When you remove the glass plate the bromine particles diffuse upwards whilst the air particles diffuse downwards, until both jars are uniformed. The air and bromine particles are moving randomly with larger gaps between them, therefore they can mix easily.
diffusion of liquid
the potasium manganate is placed in water and concentrated in one area. The crystal dissolves in water. A net movement of water occurs in the opposite direction. Eventually the crystal molectules are evenly distributed among the container.
diffusion of potasium permogante
take a becker of water and place the potasium permogante at the bottom, purple colour slowly spreads out to fill the breaker. The water and potasium mangonate 7 particles are moving randomly and the particles can slide over each other. The particles can easily mix together.
factors effection diffusion.
1. temperature
2. mass of particles
dillution of coloured sollutions
potasium mangonate 7 is a bring purple substance. It is a good example of dilution because the process is very easy to see. If you add water to the solution the potasium mangonate particles will spread futher apart. THe more water you add the more the solution will dilute and the less purple it will become. The colour fades but does not dispear.
Factors Effecting Diffusion - Temp
The higher the temperatiure the more particles of matter absorb energy making them move faster. Thereforce the rate of diffusion is higher. Lower the temp the slower the rate of diffusion
Mass of Partile - Factors of Diffusion
the lower the mass of particles the faster a gas will diffuse. The mass of a molecule in called its relative molecular mass. The lower its relative moleculer mass the faster the gas will diffuse.
relative molucular mass
the mass of a molecule
ammonium chloride
Hrdrogen chloride + Ammonia = ammonium chloride
HCl+NH3=NH4Cl
Properties of compounds
chemically bonded, cannot be physically seperated, compounds show their own characteristics, ratio of compounds are fixed. Boiling point and melting point are constant.
compounds
formed when two or more diffrent types of elements chemically combine
mixtures
a combination of two or more substances that are not chemically combined
mixtures properties
not chemically bonded, can be physically sepertated, do not show their own characteristics, ration of components may vary. Boiling point and melting point are not constant.
pure substances
contains only one substance, with no other substances mixed together. Fixed boiling points and melting points.
mixtures 2
combination of 2 or more substances that are not chemically joined together. Has a range of melting a boiling points as they consist o diffrent substances that melt or boil at diffrent temps.
eg. desolving 10g of common salt(sodium chloride)