How do we know about the structure of the atom?

Scientists originally thought that atoms were like a 'plum pudding' in that they were a sphere of positive charge with negatively charged electrons scattered about inside it. This was because they observed from experiment that the atom was neutral and also that it contained electrons. Therefore the negatively charged electrons must be cancelled out by a positive charge.

However, a scientist named Rutherford proved this model wrong by firing positively charged particles named alpha particles at some atoms in gold foil. Most of the alpha particles went straight through the foil but some were deflected back the way they had come. 

This lead to our current model of the atom where most of it is empty space, allowing most of the particles to pass straight through. The nucleus is a positively charged collection of protons and neutrons (which have no charge) and so repels the positively charged alpha particles. The electrons surround this nucleus in rings. 

KR
Answered by Katherine R. Physics tutor

3197 Views

See similar Physics GCSE tutors

Related Physics GCSE answers

All answers ▸

A bat emits a sound wave with a frequency of 25.0 kHz and a wavelength of 0.0136 metres. Calculate the speed of this sound wave.


A pendulum has a frequency of 0.80 Hz, calculate the periodic time of the pendulum.


How does conduction work in metals?


A rollercoaster carriage wants to go up a slope of length 10m at an angle of 30 degrees above the horizontal, at what speed must the carriage be travelling at the bottom of the slope in order for it to reach the top? (Negligable Drag)


We're here to help

contact us iconContact ustelephone icon+44 (0) 203 773 6020
Facebook logoInstagram logoLinkedIn logo

© MyTutorWeb Ltd 2013–2025

Terms & Conditions|Privacy Policy
Cookie Preferences