The Chemical Earth Flashcards
1.2
Identify the difference between elements, compounds and mixtures in terms of particle theory
Elements: all atoms are the same, properties are always the same
Compounds: contains identical clusters of two or more different atoms
Mixtures: ingredients retain properties and can be separated
1.3
Identify mixtures, elements and compounds in earth’s spheres
Biosphere: Nucleic acids, fats
Lithosphere: free elements (gold, platinum), minerals
Atmosphere: mixture of gases
Hydrosphere: water, dissolved sea salts
1.4
Identify and describe procedure and property that separates solids of different sizes
Sieving
Difference in particle size
1.4
Identify and describe procedure and property that separates dissolved solids in liquids
Evaporation
Different boiling points
1.4
Identify and describe procedure and property that separates solids and liquids
Filtration
Difference in particle size
1.4
Identify and describe procedure and property that separates liquids
Decantation
Density
1.4
Identify and describe procedure and property that separates gases
Distillation
Boiling points
1.5
What is gravimetric analysis and why is it needed?
It is used to determine quantities by mass of substances present in a sample.
The parts are labelled as percentage compositions
2.1
What is the relationship between reactivity of an element and the likeliness of it being found naturally uncombined?
The more reactive an element is, the less likely it is to be found naturally uncombined.
2.2
What are the main properties of metals?
Lustrous, high conductivity and density
2.2
What are the main properties of semi-metals?
Low sheen, moderately dense and malleable, high thermal conductivity, low electrical conductivity (semi-conductor), high boiling point
2.2
What are the properties of non-metals?
Dull, low thermal conductivity, no electrical conductivity, low density and boiling point
2.3
Account for uses of metals in terms of physical properties
Metal e.g. Aluminium
Use for foil, cans, saucepans, roofing, because of lustre, malleability, corrosion-resistance
2.3
Account for uses of non-metals in terms of physical properties
They have a large range of properties, so have various uses
2.3
Account for uses of semi-metals in terms of physical properties
Also vary greatly - conductivity increased by liquids such as As or B
3.1
Describe the interaction of particles in solids
Particles are in a fixed position and are close together, but still slightly vibrate
3.1
Describe the interaction of particles in liquids
Particles roll over each other, change formation, but stay attached