Atomic structure Flashcards
what are the subatomic particles and their charges?
protons (+), neutrons (/), electrons (-)
what are the relative masses of subatomic particles?
protons- 1, neutrons 1, electrons 1/2000 (very small)
where are the subatomic particles found?
protons and neutrons in nucleus and electrons in shells which orbit
what’s an ion?
when charges in an atom aren’t balanced, different number of protons and electrons
what’s atomic mass? what’s atomic number?
- No. of protons+ neutrons
- No. of protons
How do we know two elements are the same?
if they have the same number of protons
what’s an isotope?
the different forms of an element, where the no. of protons is the same but diff no. of neutrons
how do we calculate the relative atomic mass?
sum of (isotope mass x isotope abundance) / sum of abundances
what’s a molecule?
what’s a compound?
A group of 2 or more SAME atoms, chemically bonded
A group of 2 or more DIFFERENT atoms, chemically bonded
Define mixture.
Two or more substances NOT chemically combined but together in the same space.
Describe filtration.
Uses filter paper to separate insoluable solids and liquids.
Describe evaporation + crystallization.
Separates solutions. Heat (water bath) causes solvent to evaporate, remaining solution gets more concentrated and crystals start to form.
How can mixtures be separated?
Filtration,
crystallization, simple distillation, fractional distillation and
chromatography
What is thermal decomposition?
When a substance breaks down due to heat.
Describe simple distillation.
Separates out a liquid from a solution. Heat up solution, liquid with lower BP evaporates then condenses (water jacket).
Who founded the plum pudding model?
J.J Thompson
Describe the plum pudding model
Suggested that the atom is a ball of positive charge with negative electrons embedded in it
Who found the existence of neutrons.
James Chadwick