Atom vs Molecule vs Compound - Development of the Periodic Table Flashcards
What is an atom?
The smallest part of an element that can exist
What is a molecule?
Any elements that are chemically combined, even if they are the same element e.g methane, water,ammonia (also compounds)
What is a compound?
2 or more different elements chemically combined in fixed proportion
What’s an element?
Atoms are all the same
How to calculate relative atomic mass?
(% of isotop 1 X mass of isotope 1) + (% of isotop 2 X mass of isotope 2) ÷ 100
What is relative atomic mass?
Average of the mass numbers of the different isotopes
What are isotopes?
Atoms with the same number of protons but different number of neutrons
What is relative atomic mass?
Average of the mass numbers of the different isotopes
What is a mixture?
Different elements or compounds that aren’t chemically combined
What can physical separation techniques only separate?
Mixtures only
What is filteration used for?
To separate an insoluble solid from a liquid
What is crystallisation used for?
To separate a soluble solid from a liquid
What is simple distillation used for?
To separate 2 liquids of different boiling points OR getting a liquid out of a soluble solid
Explain how simple distillation is done
- Evaporate the liquid by heating - turns liquid into a vapour
- Condense vapour by cooling so it become s a liquid
What is fractional distillation used for?
When you want to separate many liquids with different boiling points
