F331 - Module 1 - (EL) Elements of Life - Atomic structure

Syllabus


Atomic structure

(d) describe protons, neutrons and electrons in terms of their mass and relative charge

(e) describe the structure of atoms in terms of electrons and a central nucleus containing protons and neutrons

(f) explain the occurrence of absorption and emission atomic spectra in terms of changes in electronic energy levels

compare and contrast the features of these spectra:

(i) similarities: both line spectra; lines in same position for a given element;

lines become closer at higher frequencies;

sets of lines representing transitions to or from a particular level

(ii) differences: bright/coloured lines on a black background or black lines on coloured/bright background;

understand the relationship between the energy emitted or absorbed and the frequency of the line produced in the spectra;

ΔE = hƒ

(g) describe the electron structure of atoms in terms of main energy levels (electron shells), up to Z = 36;

(h) recall that the nuclei of some atoms are unstable and that these atoms are radioactive

recall and explain the different properties of alpha, beta and gamma radiations

recall that the term half-life refers to the time taken for half the radioactive nuclei in a sample to decay and that the half-life is fixed for any given isotope

carry out half-life calculations;

(i) use nuclear symbols to write equations for nuclear processes, both fusion and radioactive decay;

(j) recall that, in fusion reactions, lighter atoms join to give heavier atoms (under conditions of high temperature and pressure) and understand that this is how certain elements are formed;

(k) understand how radioactive isotopes can be used as tracers in the body and (given information) for other uses;

explain that the half-life of ¡¥tracers¡¦ must be of an appropriate length to allow detection but not cause undue damage;

understand the use of radioisotopes in the dating of archaeological and geological material;

(l) understand that knowledge of the structure of the atom developed in terms of a succession of gradually more sophisticated models; given information, interpret these and other examples of such developing models;