1. STAAR Review DAY 1 MATTER AND ENERGY
TEKS 8.5A (R), 8.5B (R), 7.5C (S), 7.6A (S), 7.6B (S)
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2. Structure of Atoms Nucleus of the Atom - Contains Protons and Neutrons
Protons, Neutrons, and Electrons
Nucleus of the Atom
- Contains Protons and Neutrons
Electron Cloud of the Atom
- Contains Electrons
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3. Protons, Neutrons, and Electrons
Take a minute to fill in the table below on a piece of paper…
Protons
Neutrons
Electrons
Mass of Particle
(1, 0)
Charge of Particle
(-1, 0, +1)
Location of Particle
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4. Protons, Neutrons, and Electrons
Is this what you came up with?
Protons
Neutrons
Electrons
Mass of Particle
(1, 0) 1
Charge of Particle
(-1, 0, +1) +1 -1
Location of Particle
Nucleus
Orbitals or Electron Cloud
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5. Makeup of an Element
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The ATOMIC NUMBER indicates the number of PROTONS in an ELEMENT
The ATOMIC MASS (rounded) indicates the number of PROTONS plus NEUTRONS
Only Oxygen has 8 protons, which makes it a unique element.
To find the number of neutrons, subtract the atomic number from the atomic mass:
16 – 8 = 8
Electrons are normally equal to the number of protons if the charge of the atom is zero.

6. Gaining (or Losing) a Charge!
Element + Element = Compound
Most elements will either gain or lose valence electrons and become charged.
Nonmetals (right side of periodic table) typically gain electrons and are negatively charged.
Metals (left side of the periodic table) typically lose electrons and are positively charged
Because metals and nonmetals are oppositely charged, these individual elements will combine to form compounds.
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7. Gaining (or Losing) a Charge!
= VALENCE ELECTRON
12 P
8 P Mg O
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8. Gaining (or Losing) a Charge!
= VALENCE ELECTRON
Lose 2 Electrons
+2 Charge
Gain 2 Electrons
-2 Charge
12 P
8 P Mg O
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9. Reactivity
The number of valence electrons will determine how reactive an element will be.
If an element has valence electrons to gain or lose, it will be very reactive.
If an element has all eight valence electrons, it is considered to be non-reactive.
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10. Chemical and Physical Changes in the Digestive System
Identify examples of physical and chemical changes that occur at each of these points. A B C
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11. Chemical and Physical Changes in the Digestive System
A – Chewing and swallowing (physical) and saliva (chemical)
B – Stomach acids breakdown proteins and fats (chemical)
C – Absorption of water (physical) and breakdown
of proteins, fats, and carbohydrates (chemical). A B C
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12. Energy and Food Webs
On a piece of paper, diagram the flow of energy through these organisms.
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13. Energy and Food Webs
SUN
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14. Organic Compounds CARBON
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Organic Compounds are compounds containing carbon.
Organic compounds are the building blocks of life, including substances like fats, sugars, and protein.
Fossil fuels are also organic compounds.
Can you identify any other carbon-containing compounds?
Hydrogen
Oxygen
Phosphorus
CARBON
Nitrogen
Sulfur

15. M K H
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