6.5- element vs. compound& 6.6- physical properties can be used for classification
Element vs. Compound Carbon
Sample Questions for SS 6.5C: 1. Which substance cannot be decomposed into simpler substances? A. ammonia (NH3) B. carbon (C) C. water (H2O) D. glucose (C6H12O6) 2. Which of the following would be found only in the Compounds side of the Venn diagram shown above? A. III, IV C. II, III B. I, VI D. IV, V
Sample Question for SS 6.6A: 3. You are testing a silver rock with the lab equipment shown in the diagram. The silver rock has a positive test. What can you narrow the sample down to? A. I C. I, II. III B. I, II D. II, III
Density Animation link
Sample Question for SS 6.6B: 4. A field geologist collected data for two nuggets of copper and determined their density. Which two pieces of equipment did the geologist most likely use to determine the density of the copper nuggets? A. a balance & a graduated cylinder B. a metric ruler & a beaker C. a thermometer & an Erlenmeyer flask D. a specimen bottle & a pair of forceps
Review of atomic structure What are these subatomic particles? Proton Neutron Electron What determines the identity of an element? The number of protons…or….the atomic number! Atomic number = number of protons
Review of atomic structure What are these subatomic particles? Proton Neutron Electron What determines the chemical properties or reactivity of an element? The valence electrons!
Sample Question for RS 8.5A: 5. Which statement best describes one of the subatomic particles that could be found at location X? A. it has mass but no charge B. it has no mass & a positive charge C. it has a large mass & a negative charge D. it has no mass & a negative charge
Valence Electrons An electron in an outer shell of an atom that can participate in forming chemical bonds with other atoms Octet Rule = 8
Sample Question for RS 8.5B: 6. Observe the diagram of a water molecule above. Choose a statement that best describes why the chemical formula for water is H2O. A. oxygen is a nonmetal & hydrogen is a gas B. the two elements bond together because both elements are gases C. oxygen has six valence electrons which bond with two hydrogen valence electrons making the last energy level complete D. hydrogen loses its valence electrons making it a negative ion, & oxygen gains those electrons making it a positive ion
Periodic Table Group= vertical column with similar chemical & physical properties (same # of valance electrons)
Periodic Table Period= horizontal row with changing chemical properties (# of protons & electrons increases from left to right)
Sample Question for RS 8.5C: 7. An element has a metallic-gray appearance. It also has the properties of both a metal and a nonmetal. In which section of the periodic table indicated above would the element most likely be found? A. 1 C. 3 B. 2 D. 4
Chemical Formulas C12H22O11 What is it? Sucrose 12 # of carbon atoms=___ # of hydrogen atoms=___ # of oxygen atoms= ___ 22 11 What does it look like?
Sample Questions for RS 8.5D: 8. The chemical formula for baking soda is made from one atom of sodium, carbon, hydrogen & three atoms of oxygen. Which of the following best represents the correct formula? A. SHCo3 B. NaHCo3 C. NaHCO3 D. NaH(CO)3 9. The chemical formula for aspirin is C9H8O4. Which best describes the number of atoms of each element in the formula? A. 9 chlorines, 8 heliums, 4 oxygens B. 9 carbons, 17 hydrogens, 21 oxygens C. 9 chlorines, 8 heliums, 21 oxygens D. 9 carbons, 8 hydrogens, 4 oxygens
Chemical Reactions Is it balanced?
Sample Questions for RS 8.5E: 10. A student observes some sugar as it is heated & burns. The student concludes that a chemical reaction has occurred. Which of the following observations about the burning sugar provides evidence of a chemical reaction? A. heat is added to the sugar crystals B. the sugar melts & becomes a liquid C. the temperature of the sugar increases D. gas is produced as the sugar turns black 11. The equation above shows the chemical reaction for burning coal. Which of the following best explains the reaction represented by this equation? A. carbon dioxide gas breaks down into solid carbon & oxygen gas B. solid carbon reacts with oxygen gas to produce carbon dioxide gas C. solid carbon, oxygen gas, & carbon dioxide gas react to form products D. oxygen gas heats solid carbon, melting the carbon into a liquid
Sample Questions for SS 8.5F: 12. Which reaction between methane gas & oxygen supports the Law of Conservation of Mass? A. CH4 + O2 --> CO2 + H2O B. CH4 + 2O2 --> CO2 + 2H2O C. 2CH4 + O2 --> 2CO2 + 2H2O D. 2CH4 + 2O2 --> 2CO2 + 3H2O 13. If 32 grams of oxygen is combined with 4 grams of hydrogen, how much water would be formed? A. 4 grams C. 32 grams B. 28 grams D. 36 grams
Sample Question for RS 8.5E: 14. A student placed 2 grams of baking soda in a balloon & 100 mL of vinegar in an Erlenmeyer flask. After stretching the opening of the balloon across the neck of the flask, the student raised it to dump the baking soda into the flask. She immediately observed foaming bubbles in the flask & the balloon began to expand. The student concluded that: A. a physical change only was occurring. B. the bubbles indicated a chemical change was occurring. C. the baking soda & vinegar were products of a chemical reaction. D. the gas that was produced was oxygen.
Food Chain Tertiary Consumer Arrow indicates transfer of energy! Snake Secondary Consumer Lizard Primary Consumer What is missing? Grasshopper Producer Decomposers! Grass
Food Web A more realistic representation!
Trophic Levels 10%
Trophic Levels 10% Rule HEAT 90%
Sample Question for SS 7.5C: 15. Choose the best statement that reflects the transformation of energy processes found within an ecosystem. A. When plants grow, they produce energy that is used by all organisms in higher levels. B. Plants are producers for an ecosystem; all organisms eat plants so energy is passed to other levels. C. The sun provides the initial energy for producers; consumers eat producers & other consumers which causes energy to be passed on to higher levels. D. Decomposers produce energy for plants by breaking down dead matter; this is the initial step towards the transformation of energy for each trophic level.
7.6- matter has physical & chemical properties & can undergo physical & chemical changes
Organic Compounds Contain Carbon + Other Elements Glucose & fructose- sugars Leucine- an amino acid Methionine- an amino acid ATP
Physical Change a change from one state (solid or liquid or gas) to another without a change in chemical composition
Chemical Change any change from one state (gas, liquid, solid) which is accompanied by alteration of the chemical composition
Physical vs. Chemical Changes in Matter- Digestive System Chewing Saliva Churning Stomach acid
Sample Question for SS 7.6B: I. Chewing & mixing food with saliva in the mouth II. Movement of food using peristalsis through the esophagus III. Reaction of food with hydrochloric acid in the stomach IV. Interaction of food with bile in the small intestine 16. Which of the following digestive processes will be found in the middle of the Venn diagram? A. I C. III B. II D. IV