Atoms, Ions, and Molecules NOTES
Atom
 All physical things, living and nonliving, are made of ______________
 Smallest basic unit of _________________________
 All atoms share the same basic_________________________
Atoms consist of three types of smaller particles:
*List below and identify their charges. Where are each located in the atom?
1.)
2.)
3.)
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Type of atom that can’t be broken down into a simpler substance __________________
List 3 examples
1.)
2.)
3.)
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Elements are identified by their number of _______________________
How can we identify the number of protons, neutrons, and electrons from this picture?
Number of protons? _____________
Number of neutrons? _____________
Number of electrons? _____________
Number of protons? _____________
Number of neutrons? _____________
Number of electrons? _____________
 What 4 elements make up 96% of the human body’s mass?
1.)
2.)
3.)
4.)
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Where are the protons and neutrons found in the atom? _____________
Where are the electrons found in the atom? ____________
What is the name of the model that shows the atoms electrons located outside the nucleus in
regions called energy levels? _____________
Bohr Model
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Different types of atoms have different numbers of ________________and energy levels.
The first energy level can ONLY have up to _______________ number of electrons.
The remaining energy levels can have up to _____________ number of electrons.
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Draw a Bohr Model of the elements oxygen and calcium
Ions vs. Isotopes
____________________ same number of protons (same element) different number of neutrons (different
mass) – Ex:Carbon-14
•  ________-an atom that gained or lost one or more of its electrons
 Why do atoms gain or lose electrons?:
o Atoms want a ______________________________(valence shell)
o What happens when an atom loses or gains electrons?
For example:
• Sodium (Na) has how many electrons? _______________________
• Chlorine (Cl) has how many electrons? _________________________
Draw the Bohr model for each
Who is closer to having a full outermost electron shell??
•
•
Na will give one of its ___________to chlorine
– Becomes Na+ = positive charge = _________________
Cl will gain an _____________ from Na
– Becomes Cl- = negative charge = _________________
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________ _________ – forms through the electrical force between oppositely charged ions
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The positive sodium ion (Na+) and negative chloride ion (Cl-) attract to each other and form
an ionic bond
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•
A _______ _____ bond forms when atoms share a pair of electrons
Draw a Bohr model for oxygen and carbon
– How many electrons does oxygen need to fill its outermost shell? _________________
– How many electrons does carbon need to fill its outermost shell? __________________
• ________________- two or more atoms held together by covalent bonds
• For example: ______________________________________________
**Almost all of the substances that make up organisms are molecules held together by covalent
bonds
• __________________- A substance made of different elements bonded together in a certain ratio
• Compounds are held together by ________________ ______________