Atoms, Isotopes, and Ions

Atoms I. Parts

• Nucleus: Protons_____________________

Neutrons _____________________• Orbiting Nucleus: Electrons _____________________

positive (+) chargeneutral (0) charge

negative (-) charge

II. Valence Electrons

Electrons on theouter _______ or ________ level

shellenergy

III. Energy Levels or Electron Shells

1st Energy Level holds ____ electrons2nd Energy Level holds ____ electrons3rd Energy Level holds ____ electrons

28

18

IV. Most elements are unstable

• If the outer shell is not full then electrons can be shared, lost or gained

• Metals tend to _____________ electrons• Nonmetals tend to ______________ OR

__________________ electrons

losegain

share

V. Practice

Element#

Protons#

Electrons#

Valence Electrons

Electrons: Share, Lose, Gain or

Stable Atom Hydrogen

Helium

Fluorine

Neon

Carbon

1 1 1 Share, Lose, or Gain

2 2 2 Stable Atom

9 9 7 Gain

10 10 8 Stable Atom

6 6 4 Share

IsotopesI. What makes an element different?

• Elements can have different numbers of _______• Rule reminder: Mass # – #________________ = # neutrons

Element Isotope # Protons # Electrons Mass # # NeutronsCarbon C-12

C-14

protons

protons

6 6 12 6

6 6 14 8

II. Isotope

• Isotopes are atoms of the same element that have different numbers of _________________

• The atomic mass is the weighted average mass of the mixture of _________________ of an element

neutrons

isotopes

III. Practice

Element Isotope # Protons # Electrons Mass # # Neutrons

Hydrogen 1H Protium

2H Deuterium

3HTritium

1 1 1 0

1 1 2 1

1 1 3 2

Practice

Element Isotope # Protons # Electrons Mass # # Neutrons

Boron 10B

11B

5 5 10 5

5 5 11 6

# Neutrons?

6 7 8

IonsI. Charges of Elements on the Periodic Table

• Atoms on the periodic table are ______________________

• Therefore the positive charges equal the _________________________ charges

• # _________ = # __________

neutral

negative

protons electrons

II. Charges of Elements in Nature

• Most atoms are ___________________ therefore they will share, lose or gain electrons

• An atom that loses electrons will have more __________________ charges

• An atom that gains electrons will have more __________________ charges

unstable

positive

negative

III. What is an Ion?• An ion is a ______________ atom

• An atom can ______ or ______ electrons

• Cation: + ion• Anion: - ion

charged

gain lose

IV. Practice

Element # Protons # Electrons # Valence Electrons

Metal or Nonmetal

Lost or Gained

New # Electrons

Ion

Sodium

1 Metal - lose 1 lost 10 Na+1

Chlorine

7 Nonmetal - gain 1 gained 18 Cl -1

Magnesium

2

Oxygen

6

Lithium

1

Fluorine

7

11 1117 1712 12 Metal 2 lost 10 Mg+2

8 8 Nonmetal 2 gained 10 O-2

3 3 Metal 1 lost 2 Li+

7 7 Nonmetal 1 gained 8 F-

When there is a change in ___ it forms a(n) ___

# of protons ________________________

# of neutrons _______________________

# of electrons _______________________

different element

isotope

ion