Science 1B Chapter 8
Structure of an Atom
Proton
Neutron
Electron
Location
Charge
Mass
Location
Charge
Mass
Location
Charge
Mass
Periodic Table
Molecules
Atom
Simplest unit of an element
One of the largest atoms, a caesium atom, has the size of about 0.000000007cm
Negligible (1/1840)
Around the nucleus in an electric field
Negative 1 (-1)
In the nucleus
Positive 1 (+1)
1
In the nucleus
Neutral (0)
1
Neutrally charged
Some types of atoms have different numbers of neutrons, making their average mass, the mass seen in the Periodic Table, to have a decimal (e.g Chlorine 35.5 [1dp])
Mass of atom/ Mass of nucleus = No. of proton + no. of neutrons
Elements are arranged in the Periodic Table by their proton number (increasing)
2 or more atoms chemically combined, can be with same element of with different elements