topic 1 recap Q. atomic structure Flashcards
what is an atom?
smallest part of an element that can exist
What is Daltons model of an atom?
atoms as solid spheres that could not be divided into parts
What is the plum pudding model?
Sphere of positive charge with negative electons embedded in it
What did scientists discover in the alpha scattering experiment?
Small central nucleus with electrons orbiting
some alpha particles were deflected by the gold foil
Describe the nuclear model of the atom
Dense nucleus with electrons orbiting it
What did Neils Bohr discover
electrons orbit in fixed energy levels (shells)
What did James Chadwick discover
uncharged particle called the neuron
how can you find out the number of protons in an atom?
the atomic number on the pt
how to calculate the number of neutrons in an atom?
mass number-atomic number
what is an element?
a substance made of one type of atom.
What is a compound?
substance made of more than one type of element chemically joined together.
what is isotopes?
atoms with the same number of protons but a different number of neutrons.
5 physical processes that can be used to separate mixtures?
filtration
crystallisation
distillation
fractional distillation
chromatography
What is relative mass?
the average mass of all the atoms of an element.
