Chapter 4

Which of the following statements are consistent with Rutherford's nuclear theory as it was originally stated?

- The volume of an atom is mostly empty space. -Atomic nuclei are small compared to the size of atoms.

On the basis of Rutherford's experimental observations, which of the following statements predicts the structure of the atom?

-In an atom, most of the mass and the positive charge are located in a small core within the atom called the nucleus. -In an atom, negatively charged electrons are dispersed in the space surrounding the positively charged nucleus of an atom.

Conclusions of Rutherford's experiment

-The atom contains a positively charged nucleus -A positive charge is condensed in one location within the atom -The majority of the space inside the atom is empty space

Electrons :

-have a charge of 1- -if an atom has an equal number of protons and electrons, it will be charge-neutral -experience an attraction to protons

Sort each of the items into the appropriate bin. Use the diagram of a neutral lithium atom, shown to the left, for reference.(Figure 1) Drag each item to the appropriate bin.

Proton: Particle labeled "B" +1 charge approximately the same mass as a neutron Neutron: Particle labeled "A" no charge Electron: Particle labeled "C" -1 charge smallest mass of the three particles

Mass of ~ 1 amu

Protons and neutrons

mass of electron

about 5.5 x 10^-4 amu or ~ 1/2000 amu