Chemistery Flashcards
What are the 5 steps to lighten a bunsen burner?
Put the Bunsen burner on a heatproof mat Join the Bunsen burner to a gas tap Close the air hole Light a wooden splint and hold it over the chimney Turn on the gas tap
What colour is the non-luminous flame(from bunsen burner)
Blue
What colour is the luminous flame(from bunsen burner)
yellow
Which flame is easier to see(from the Bunsen burner)
Luminous flame
What does this safety signal mean: Flammable
Any substance that will burn if exposed to an open flame.
What does this safety signal mean: Explosives
A substance that may explode if exposed to an open flame
What does this safety signal mean: Toxic/poison
This is a chemical that can lead to death if inhaled, ingested or absorbed by the skin.
What does this safety signal mean: Corrosive
A substance that can destroy or burn living tissue and can eat away other materials.
What does this safety signal mean: Irritant
A substance that causes inflammable upon contact with skin or mucous membrane
What does this safety signal mean: Environmental
Substances that are harmful to the environment. They must get rid of properly not down the sink.
What does this safety signal mean: Harmful
The substances are similar to toxic substances but are less dangerous.
What does this safety signal mean: Oxidising
These substances provide oxygen allowing them to burn more fiercely.
Properties of solid
Have a high density because particles are closely packed together
Cannot be compressed because of really little space between particles
Have a fixed shape because particles are held together
Cannot diffuse because particles are not able to move
Properties of liquids
Have a fairly high density because the particles are close together
Cannot be compressed there is very little empty space between particles
Take up the shape of the container because particles can move
Can diffuse because particles can change places
Properties of gases
Have a low density because particles are spaced far apart
Can be compressed because there is space between particles
Don’t have a fixed shape because the particles move rapidly in all directions
Can diffuse because particles can change places
Protons
positively charged particles found in the nucleus of an atom
Neutrons
Neutral particles found in the nucleus of an atom
Electron
Negatively charged particles that orbit the nucleus
Charge and mass of a proton
Mass= 1, Charge= +1
Charge and mass of an electron
Mass= very small, Charge= -1
Charge and mass of a neutron
Mass=1, Charge= 0
Full form RF and how to work it out
Retention factor. RF= distance from the base line to the spot/ distance from the base line to the solvent front
What is the RF used for?
is used to compare the components of various values.
Conversation of mass
The law of conversation of mass stated thus: In a chemical, reaction, matter neither created or destroyed.
Which scientist discovered the conversation of mass
Antoine Laurent Lavoisier
What are the four separation techniques?
Chromatography, Filtration, Distillation, Crystallysastion
Atom
The smallest part of an element that can exist
How many maximum numbers of electrons can be put in a shell: first shell, second shell, the third and fourth shell
1st: 2, 2nd: 8, 3rd: 8, 4: 2
John Dalton
Pre 1900. Solid spheres cannot be divided and before the discovery of the electron, he said they are made up for their different elements.
Pre 1900. Solid spheres cannot be divided and before the discovery of the electron, he said they are made up for their different elements.
John Dalton
When: A ball of positive charge with negative electrons embedded in it. JJ Thompson’s experiment showed an atom must contain a negative charge( discovery of the electron)
1897’ Plum pudding model’
1897’ Plum pudding model’
A ball of positive charge with negative electrons embedded in it. JJ Thompson’s experiment showed an atom must contain a negative charge( discovery of the electron)
1909’ Nuclear model’
Positively charged nucleus at the centre surrounded by negatively charged electrons. Earnest Rutherfud’s alpha particle scattering experiment showed that the mass was concentrated at the centre of the atom.
Positively charged nucleus at the centre surrounded by negatively charged electrons. Earnest Rutherfud’s alpha particle scattering experiment showed that the mass was concentrated at the centre of the atom.
1909’ Nuclear model’
1913’ Bohr model’
Electrons orbit the nucleus at specific distances. Niels Bohr proposed that electrons orbit the nucleus in fixed shells and this was supported by experimental observations.
Electrons orbit the nucleus at specific distances. Niels Bohr proposed that electrons orbit the nucleus in fixed shells and this was supported by experimental observations.
1913’ Bohr model’
James Chadwick
Provided the evidence to show the existence of a neutron
who provided the evidence to show the existence of a neutron
James Chadwick
What’s Rutherford’s scattering experiment
Beams of alpha particles are directed at a very thin gold foil. Most of the alpha particles passed right through. A few alpha particles were deflected by the positive nucleus. A tiny number of particles reflected back from the nucleus.
Filtration with example
separating an insoluble solid from a liquid. e.g To get sand from a mixture of sand, salt, and water.
Crystallisation with example
To separate a solid from a solution. e.g to obtain pure crystals of sodium chloride from salt water.
separating an insoluble solid from a liquid. e.g To get sand from a mixture of sand, salt, and water.
Filtration
To separate a solid from a solution. e.g to obtain pure crystals of sodium chloride from salt water.
Crystallisation
Simple Distillation with e.g
To separate a solvent from a solution. e.g to get pure water from salt water.
To separate a solvent from a solution. e.g to get pure water from salt water.
Simple Distillation
Fractional distillation with e.g
Separating a mixture of liquids each with different boiling points. e.g to separate the different compounds in crude oil.
Separating a mixture of liquids each with different boiling points. e.g to separate the different compounds in crude oil.
Fractional distillation
Chromatography with e.g
Separating substances that move at different rates through a medium. e.g to separate dyes in food colouring.
Separating substances that move at different rates through a medium. e.g to separate dyes in food coloring.
Chromatography
Metals and their properties
to the left of the periodic table conductors high melting and melting point ductile malleable
Non-metals and their properties
to the right of the periodic table
insulators
low melting and boiling point
does the melting and boiling point in increase or decrease as you go down the group 7
increase
does the reactivity increase or decrease as you go down group 7
decrease
What will happen to the less reactive halogen that has reacted with a element with a more reactive halogen
The more reactive halogen will displace the more reactive element e.g. Chlorine +potassium bromide ( arrow to the right) potassium chloride + bromine.
What is the same thing that a element in a certain group has?
Number of electrons in a outer shell.
