Parts of the Atom & Vocab
What is the center of an atom (the part that holds everything) called?
The nucleus
Which subatomic particle does a Bohr model represent (which ones are we actually drawing)?
Electrons
What does the number at the top of an element represent? What does the number at the bottom mean?
Top = Atomic number = # of protons
Bottom = atomic mass = Protons + Neutrons
Liquid water being turned into a gas is called __________
Vaporization
Which is more easily reversible: physical or chemical changes?
Physical
What are the three types of subatomic particle?
Proton, Neutron, Electron
How many electrons can be stored in the INNER MOST shell of an element? How many can be stored in the next shell?
Inner = 2
Next shell = up to 8
How do I find the number of neutrons in an element? How many neutrons does Carbon (atomic # 6, atomic mass 12) have?
Subtract protons from neutrons.
Neutrons = 12 - 6 = 6
When a substance goes directly from a solid to gas, we call this ___________
Sublimation
Provide ONE example of a chemical change
Mixing two chemicals, digesting food, rusting a nail, burning a log
What are the CHARGES of the three types of subatomic particles?
Proton = Positive
Neutron = Neutral
Electron = Negative
What is a valence electron? What does it actually do, in terms of chemicals having a reaction?
Electron in the outermost shell
Transfers charges from one substance to another
What are the ROWS on the periodic table called? What are the COLUMNS called?
Rows = Periods
Columns = Groups
In terms of energy and molecules of a liquid, how do phase changes occur? Are they physical or chemical changes?
Molecules take heat energy and begin vibrating/moving more rapidly and begin to change phases
Physical change because nothing new is formed (boiled water is still just water)
Is reactivity with water or air a chemical or physical property?
Is flammability a physical or chemical property?
Reactivity = chemical
Flammability = chemical
In the nucleus (the center)
Draw a Bohr Model of the element Boron, and show Mr. Breeden when you're finished. How many valence electrons are there on Boron?
3 valence electrons
As each period increases, what increases with each element in the period?
The number of shells / electrons able to bond
List THREE examples of physical properties of an object.
Solubility, touch, smell, taste, color, phase changes, density, hardness, texture
What does the Law of Conservation of Matter mean? (hint: think about our last unit, and it's law of conservation... or exploding whales.)
Matter cannot be created or destroyed
Where do we find electrons in an atom?
BONUS: What do we call electrons in the outermost shell?
Electrons orbit the atom in shells
Bonus = Valence Electrons
Draw a Bohr model for the element Chlorine. Show Mr. Breeden your finished drawing. Tell us how many valence electrons there are.
BONUS: What is the OXIDATION # of Cl?
Valence electrons = 7
Oxidation # = -1
What group of elements on the periodic table does NO BONDING?
BONUS: Why don't they form bonds with other elements? Your answer should include valence electrons/the octet rule.
Noble Gases
Don't bond because outermost shell is already full; no need to bond
List THREE examples of something that use chemical properties.
BONUS: what are TWO characteristics of a chemical change that make them different form a physical change?
Properties: reactivity, burning, toxicity, radioactive, rusting, digesting, rotting, oxidizing
Chemical changes cannot be undone, produce something new
Define and explain each part of EPOCH
BONUS: What does it mean (in terms of heat) if a reaction is exothermic? Endothermic?
E - Effervescence - BUBBLES
P - Precipitant - Powder
O - Odor - change in smell
C - Color change - change in color
H - Heat - exothermic and endothermic
Exothermic = releases heat
Endothermic = absorbs heat (gets colder)