Everything Science Grade 10

CHAPTER 4. THE ATOM 4.3

and measured its mass.

Other models of the atom ESAAT

Although the most commonly used model of the atom is the Bohr model, scientists are

still developing new and improved theories on what the atom looks like. One of the most

important contributions to atomic theory (the field of science that looks at atoms) was the

development of quantum theory. Schrodinger, Heisenberg, Born and many others have

had a role in developing quantum theory.

Exercise 4 - 1

Match the information in column A, with the key discoverer in column B.

Column A Column B

1.Discovery of electrons and the plum pudding model A.Niels Bohr

2.Arrangement of electrons B.Marie and Pierre Curie

3.Atoms as the smallest building block of matter C.Ancient Greeks and Dalton

4.Discovery of the nucleus D.JJ Thomson

5.Discovery of radiation E.Rutherford

More practice video solutions or help at http://www.everythingscience.co.za

(1.) 000k

Atomic mass and

diameter

ESAAU

It is difficult sometimes to imagine the size of an atom, or its mass, because we cannot see

an atom and also because we are not used to working with such small measurements.

Chemistry: Matter and Materials 67