Atomic Structure 1 Flashcards
Name the 3 types of a particle found in an atom
Proton, neutron electron
What is a mass number
Total number of protons + total number of neutrons
What is an atomic number?
 number of protons
What are isotopes?
 The same element of a different neutron number
Why do isotopes have the same chemical properties? 
Same number of electrons
Why do some isotopes have different physical properties?
 physical properties depend on mass
At the start of the 19th century, what did John Dalton describe atoms as?
 solid spheres
 in 1890 7,JJ Thompson created a new model. What was it called?
 plum pudding model
In 1909, Rutherford  conducted an experiment, his famous gold foil experiment, explain what he did.
 he fired alpha particles at a very thin sheet of gold I see particles are deflected showing that there was a
positively charged nucleus in the middle
What is the biggest difference between bohrs model compared to the previous?
Bohrs model has electron shells
 what is inaccurate about bohrs model
Bohrs model does not include subshells
relative isotopic mass- The average mass of an _______ when measured on a scale on which the mass of an atom of 12c is exactly 12
isotope
relative molecular mass- The average mass of an _______ when measured on a scale on which the mass of an atom of 12c is exactly 12
molecule
real atomic mass- The average mass of an _______ when measured on a scale on which the mass of an atom of 12c is exactly 12
element
An atom’s ____ number determines which element it is
Proton
