Activity 3 1-10-11

What is an atom?
An atom is the smallest component of an element having the chemical properties of the element. The atom is a basic unit of matter consisting of a dense, central nucleus surrounded by a cloud of negatively charged electrons

What are the particles that make up an atom, list their mass and charge?
Protons-positive charge
Neutrons-no charge
Electrons- negative charge

What is the size of an atom?
The size of an atom is approximately 100 pictometers or 0.1 nanometer. The size depends on the composition of an atom.

What is the shape of an atom, where are the particles?
The shape of an atom is spherical. The shape of atoms is determined by the shape of the electron orbitals (electron clouds). The protons and neutrons are in the center of the atom in the nucleus and the electrons float outside the nucleus. 
What are the characteristics of electrons?
The electron is a subatomic particle that carries a negative electric charge. It has no known components or substructure, and therefore is believed to be an elementary particle.