Why did scientific models of atomic and nuclear structure change over time?
New evidence became available.
AQA GCSE Combined Science: Trilogy (8464) — Chemistry — Higher · 5.1.1.3
Revise AQA GCSE Combined Science: Trilogy (8464) — Chemistry — Higher specification point 5.1.1.3, The development of the model of the atom (common content with physics), with free active-recall flashcards. Flip through the set or review every question and answer below.
1 / 7
Why did scientific models of atomic and nuclear structure change over time?
New evidence became available.
How did the plum pudding model represent an atom?
Positive charge was spread through the atom, with electrons embedded in it.
How did Rutherford’s nuclear model represent the distribution of positive charge and mass?
Positive charge and most of the mass were concentrated in a small central nucleus.
Before the neutron was discovered, which particles were sometimes thought to make up nuclei?
Protons and electrons.
Who discovered the neutron, and in what year?
Chadwick, in 1932.
What model of the nucleus did Chadwick’s discovery support?
Nuclei contain protons and neutrons.
Why can nuclei of the same element have different masses?
They have the same number of protons but different numbers of neutrons.