The atom, the Nucleus and Radioactivity

Description

Leaving certificate Science Mind Map on The atom, the Nucleus and Radioactivity, created by ainearrigan on 16/03/2015.
ainearrigan
Mind Map by ainearrigan, updated more than 1 year ago
ainearrigan
Created by ainearrigan about 9 years ago
10
0

Resource summary

The atom, the Nucleus and Radioactivity
  1. The atom
    1. The plum pudding model
      1. Rutherfords expt.
        1. he believed the model and expected the alpha particles to go through the gold foil
          1. results - atoms are composed mainly of empty space have an extremely positive centre
            1. thought that there was an electron cloud surrounding the nucleus
          2. the arrangement of electrons
            1. Neils Bohr - believed electrons existed in 'energy levels' this was proofed by the emission spectrum
              1. types of spectra
                1. Continuous produced by a liquid or solid a continuous spectrum is emitted unable to detect the element stic
                  1. a line spectrum is produced by gaseous matter, it is charateristic
                  2. Emission spectrum
                    1. every element gives out its own unique emission spectrum
                      1. LASERS- Light amplification by stimulated emission of radiation
                        1. Produce an intense beam of light, the electrons recive energy and go to the same energy level and then emit the same wavelength photon
                          1. used to treat eye problems
                            1. used for telecommunication in optical fibers
                              1. used in welding and cutting
                                1. used in target designation
                            2. E2-E1=hxf
                              1. E2-E1 (difference in energy levels) h= planks constant f=frequency
                              2. c= f x ^
                              3. Bohrs theory
                        2. Radioactivity
                          1. Henri Becquerel discovered that a crystal of uranium was emitting some kind of light. Marie Curie later went on to research more and name this occurance as radiation.
                            1. natural radiation - the spontaneous decay of a nucleus, with the emission of some form of radiation
                              1. artificial radioactivity- radioactivity from atoms caused b nuclear bombardment
                                1. The activity of the radioactive nucleus
                                  1. the number of nuclei of a radioactive sample decaying per second= activity (A) / Becquerel (Bq)
                                  2. The law of radioactive decay
                                    1. no. of nuclei decaying at that moment is proportional to the no. undecayed @ that instant
                                      1. RATE OF DECAY= ^ x N
                                        1. N- the no. of undecayed atoms ^ - decay constant
                                          1. each isotope has its own decay constant
                                            1. the rate decreases as time goes on
                                              1. Half- life (T 1/2) - the time taken for half of the undecayed atoms in an sample of the element to decay
                                        2. Detecting nuclear radiation and uses
                                          1. Geiger-Muller tube or solid state detector
                                            1. - radiation passes through the window of the tube and ionises the gas - the e- are accelerated towards the anode causing more ionization -this induces a small current which measures the pulse time for each ionizing particle -it cant tell the type of radiation
                                            2. medical - cancer treatment
                                              1. carbon dating (c-14)
                                                1. used in fertilisers
                                                  1. preservation of spices in food
                                                  Show full summary Hide full summary

                                                  Similar

                                                  Using GoConqr to study science
                                                  Sarah Egan
                                                  Junior Cert Physics formulas
                                                  Sarah Egan
                                                  Units of measurement - physics
                                                  Sarah Egan
                                                  JC Science: Force, Work and Power
                                                  Bubble_02
                                                  AQA Physics P1 Quiz
                                                  Bella Statham
                                                  GCSE AQA Physics - Unit 3
                                                  James Jolliffe
                                                  Physics Revision
                                                  Tom Mitchell
                                                  GCSE AQA Physics 1 Energy & Efficiency
                                                  Lilac Potato
                                                  OCR Physics P4 Revision
                                                  Dan Allibone
                                                  Energy, Mass, & Conversions
                                                  Selam H
                                                  GCSE Physics P7 (OCR) - Light, Telescopes, and Images
                                                  Josh Price