3.1.1 Atomic Structure Knowledge Flashcards
what is the relative mass of a proton?
1
what is the relative mass of a neutron?
1
what is the relative mass of an electron?
1/1840
what is the relative charge of a proton?
1+
what is the relative charge of a neutron?
0
what is the relative charge of an electron?
1-
what is the atomic number?
total number of protons in an atom
what is the mass number?
total number of protons and neutrons in a nucleus
what is an isotope?
an atom with the same number of protons but different number of neutrons
why do isotopes have similar chemical reactions?
isotopes of the same element have the same chemical properties because they have the same electron configuration
what is a positive ion?
cation
what is a negative ion?
anion
when was the Solid Sphere model invented?
1803
who invented the Solid Sphere model?
John Dalton
summarise the solid sphere model
- All matter is composed of extremely small particles called atoms.
- Atoms of a given element are identical in size, mass, and other properties. Atoms of different elements differ in size, mass, and other properties.
- Atoms cannot be subdivided, created, or destroyed.
when was the plum pudding model invented?
1904
who invented the plum pudding model?
jj thomson
summarise the plum pudding model
- electrons embedded in a uniform sphere of positive charge.
- The positive matter was thought to be jelly-like.
- The electrons were somewhat mobile. As they got closer to the outer portion of the atom, the positive charge in the region was greater than the neighbouring negative charges and the electron would be pulled back more toward the centre region of the atom.
when was the nuclear model invented?
1911
who invented the nuclear model?
ernest rutherford
summarise the nuclear model
a small and dense positively charged nucleus surrounded by a cloud of electrons.
when was the planetary model invented?
1913
who invented the planetary model?
niels bohr
summarise the planetary model
small positive nucleus with electrons orbiting the nucleus in energy shells