Movement of Particles Flashcards
(6 cards)
1
Q
what is diffusion?
A
the gradual movement of particles from places of high concentration to places of low concentration
2
Q
potassium manganate (VII) and water experiment
A
- take a beaker of water and place some potassium manganate (VII) at the bottom - the purple colour slowly spreads out to fill the beaker
- the particles of potassium manganate (VII) are diffusing out among the particles of water
- its the random motion of particles in a liquid that causes the purple colour to eventually be evenly spread out throughout the water
NOTE: if you were to add more water to the final purple solution, the potassium manganate (VII) particles would spread out even further apart and the solution would be less purple - this is called dilution
3
Q
what colour is potassium manganate (VII)?
A
bright purple
4
Q
ammonia and hydrogen chloride experiment
A
- aqueous ammonia gives off ammonia gas, and hydrochloric acid gives off hydrogen chloride gas
- this experiment forms a white ring of ammonium chloride in the glass tube
- the ammonia gas diffuses from one end of the tube and the hydrogen chloride gas diffuses from the other - when they meet they react to form ammonium chloride
- the ring doesn’t form exactly in the middle of the glass tube - it forms nearest the end of the tube where the hydrochloric acid was
- this is because the particles of ammonia are smaller and lighter than the particles of hydrogen chloride, so they diffuse through the air more quickly
5
Q
bromine gas and air experiment
A
- bromine gas is a brown, strongly smelling gas and can be used to demonstrate diffusion in gases
- fill half a glass jar with bromine gas, and the other half of air - separate the gases with a glass plate
- when you remove the glass plate, brown bromine gas with diffuse slowly through the air
- the random motion of the particles means that the bromine will eventually diffuse right through the air
6
Q
what colour is bromine gas?
A
brown
