Atoms and Elements Notes

• What are the three parts of the atom and the charges they have?

– Proton: positive charge (+)

– Neutron: no charge (N)

– Electron: negative charge (-)

Atoms and Elements Notes

• How do we interpret the numbers for each element on the periodic table?

• Atomic number: # of protons in an element, this is what makes an element unique

• Atomic mass: # of protons + # of neutrons

• # of protons = # of electrons

Atoms and Elements Notes

• How can atoms vary, but still be the same element?

– Isotopes: different number of neutrons

– Ions: different number of electrons

• cations have fewer electrons (positive charge)

• anions have more electrons (negative charge)

Atoms and Elements Notes

• What is the Bohr model?

• What are the different layers of electrons called?

• What is the Octet rule?

• a design of what the atom would look like

• A shell is the “layer” of electrons

• In order to have the shell be “full” it has the number of elements in that row on the periodic table

Compounds and Mixtures

• What is the difference between a compound and a mixture?

• A compound is two or more elements that combine to form something new.

• A mixture is two or more elements that combine and keep their original properties.

Chemical Bonds

• What is a chemical bond?

• the way two elements attach together

Chemical Bonds

• What are the different types of chemical bonds?

– Ionic bonds: where one element takes electrons away from another

– Covalent bonds: where elements share electrons

– Diatomic molecule: where two of the same elements bond together