C1 Better Flashcards
What are the rules for writing the symbols of elements?
First letter is a capital any others are lower case.
What is the list of all the elements called?
The periodic table
What is a compound?
2 or more elements chemically bonded together and so will have different properties to the elements on their own.
What is a mixture?
2 or more elements or compounds that are not chemically bonded so each part keeps its original properties.
What is an element?
A group of atoms that are the same.
Is gold an element, mixture or compound? Why?
Gold is an element as it is made only of gold atoms.
Is carbon dioxide an element, mixture or compound? Wy?
Carbon dioxide is a compound as it is formed from carbon and oxygen chemically bonded together.
Is salt water an element, mixture or compound? Why?
Salt water is a mixture as the water compound and salt compound are not bonded together.
How many atoms are in H2SO4?
H=2 S=1 O=4 Total= 7
How many atoms are in 3HNO3?
3H + 3N + 9O –> 15
What property does filtration exploit?
Solubility
What property does crystallisation exploit?
Boiling point
What property does simple distillation exploit?
Boiling point
What property does fractional distillation exploit?
Boiling point
What separation technique separates solids from liquids?
Filtration
What are the key steps of distillation?
Heating, evaporation, cooling, condensing
Advantages of simple distillation over fractional distillation?
Simpler setup, faster, consumes less energy
Disadvantages of simple distillation over fractional distillation?
Requires the liquids to have a large difference in boiling point and gives poorer separation.
Why do inks separate in chromatography?
Because of their mass and solubility.
What is the soluble part of a filtered mixture called?
Filtrate
What is the insoluble part of a filtered mixture called?
Residue
Why would you use filtration to separate a mixture of sand and water?
Because the water will filter through but the sand is not soluble so will form the residue.
Why would filtration not be a good method to separate salt and water?
Because salt is soluble in water so both the salt and the water would be in the filtrate.
What method would be suitable to separate a mixture of inks?
Chromatography as the ink particles will have different masses so travel different distance up the filter paper.
What was the plum pudding model of the atom?
Atoms were spheres with negatively charges electrons embedded in them
Which model of the atom was developed first?
The plum pudding model was developed before the nuclear model of the atom.
What is the nuclear model of the atom?
Atoms have a central nucleus and are surrounded by negative electrons.
What caused the development of the nuclear model?
The alpha particle scattering experiment which showed that most of the mass of an atom was in a central nucleus.
Who discovered the electrons?
Thompson in 1897
Who discovered the nucleus?
Rutherford in 1911 using the alpha scattering experiment.
Who discovered the nucleus?
Rutherford in 1911 using the alpha scattering experiment.
Who discovered the number of electrons on each shell?
Chadwick in 1932