Final Jeopardy (Ch 1-6)

1. Final Jeopardy (Ch 1-6)

2. Introduction 1 Chemistry is the science of matter. Matter is defined as anything which meets two criteria. What are those criteria?

3. Introduction 1 Chemistry is the science of matter. Matter is defined as anything which meets two criteria. What are those criteria? Matter is anything that has mass and occupies space.

4. Introduction 2 Science is the practice of the scientific method. This method has four steps. First we collect observations, then we propose a tentative explanation of those observations. The third step is experimentation, and the fourth is refining our explanation. After that we go back to step 3 (the process continues indefinitely). What do scientists call their tentative explanation, what do they call a refined explanation they’ve come to trust?

5. Introduction 2 Science is the practice of the scientific method. This method has four steps. First we collect observations, then we propose a tentative explanation of those observations. The third step is experimentation, and the fourth is refining our explanation. After that we go back to step 3 (the process continues indefinitely). What do scientists call their tentative explanation, what do they call a refined explanation they’ve come to trust? A hypothesis is a tentative explanation. After we’ve experimented, tested, and come to trust an explanation we call it a theory. But a theory can always be improved upon, it’s never the end of the story. Significant observations that have no exceptions, but can’t be explained are summarized as the laws of science.

6. Introduction 3 Matter has three states—the same sample of matter can exist as a solid, a liquid, or a gas. Consider the properties of matter in these different states. How is a sample different in the solid state than when it’s in the liquid state? How is it the same in the solid and liquid state, but different when the same matter is in the gas state?

7. Introduction 3 Matter has three states—the same sample of matter can exist as a solid, a liquid, or a gas. Consider the properties of matter in these different states. How is a sample different in the solid state than when it’s in the liquid state? When matter is solid it’s shape is definite and locked, shape is indefinite in the liquid state. How is it the same in the solid and liquid state, but different when the same matter is in the gas state? Whether a sample is in the solid or liquid state, it’svolume is definite and measurable. In the gas state volume varies to fill any container holding it.

8. Introduction 4 Brewed coffee is made from coffee beans. Both substances are of interest to chemists. Classify each substance, indicate if it’s pure or a mixture—and if it’s a mixture say why it’s either homogeneous or heterogeneous.

9. Introduction 4 Brewed coffee is made from coffee beans. Both substances are of interest to chemists. Classify each substance, indicate if it’s pure or a mixture—and if it’s a mixture say why it’s either homogeneous or heterogeneous. Brewed coffee is a mixture, it has variable properties. Some coffee is stronger than others, some has more caffeine. Substances with variable properties are mixtures. But every part of a cup of brewed coffee is the same—the same taste, texture, state, color, etc. Brewed coffee is homogeneous. Coffee beans are also mixtures, but each bean is not just different from the next bean. The beans themselves have different parts (meat, veins, skin), separated by physical boundaries—phases. Coffee beans are heterogeneous.

10. Measurement 1 Look at the graduated cylinder below. What volume should you record?

11. Measurement 1 Look at the graduated cylinder below. What volume should you record? One fair estimate would be: 6.65 ml You must estimate between the certain marks!

12. Measurement 2 Two different instruments were used to measure a weight. The student wrote the readout from each instrument five times, readings were taken a second apart. If you were the student, what weight would you record for each measurement? Instrument 1 Instrument 2 23,000,013 grams 23,101,179 grams 23,000,011 grams 23,059,320 grams 23,000,002 grams 23,114,371 grams 23,000,009 grams 23,042,998 grams 23,000.001 grams 23,032,613 grams

13. Measurement 2 Two different instruments were used to measure a weight. The student wrote the readout from each instrument five times, readings were taken a second apart. If you were the student, what weight would you record for each measurement? Instrument 1 Instrument 2 23,000,013 grams 23,101,179 grams 23,000,011 grams 23,059,320 grams 23,000,002 grams 23,114,371 grams 23,000,009 grams 23,042,998 grams 23,000.001 grams 23,032,613 grams certain uncertain certain uncertain 2.30 x 107grams 2.300000 x 107grams

14. Measurement 3 A rope measures 38.50 feet, using the conversion factor 1 inch = 2.54 cm and dimensional analysis determine that length in meters.

15. Measurement 3 A rope measures 38.50 feet, using the conversion factor 1 inch = 2.54 cm and dimensional analysis determine that length in meters. 1.18 x 101 m

16. Measurement 4 A graduated cylinder has 90.00 mL of water in it. After adding a piece of metal, the new volume is recorded as 120.0 mL. If the metal has a density of 16.66 g/mL — how much did the sample weigh?

17. Measurement 4 A graduated cylinder has 90.00 mL of water in it. After adding a piece of metal, the new volume is recorded as 120.0 mL. If the metal has a density of 16.66 g/mL — how much did the sample weigh? 120.0 mL 90.0 0 mL 30.0 mL 500. mL or 5.00 x 102 mL

18. Elements 1 There are 118 known elements, most of which you’ve never experimented with. Yttrium, Antimony, and Radon for example. But you know which of these is shiny, which is brittle, and which one is a semi-conductor. Tell us.

19. Elements 1 There are 118 known elements, most of which you’ve never experimented with. Yttrium, Antimony, and Radon for example. But you know which of these is shiny, which is brittle as a solid, and which one is a semi-conductor. Tell us. Yttrium is a metal, metals tend to be shiny. Radon is a gas at room temperature, but when solid it would be brittle (most non-metals are brittle). Antimony is one of the metalloids, which are semi-conductors of heat and electricity.

20. Elements 2 A molecule of Ca(NO3)2 contains how many elements? How many atoms are in each molecule?

21. Elements 2 A molecule of Ca(NO3)2 contains how many elements? (3) How many atoms are in each molecule? (9)

22. Elements 3 A substance contains 11.2% hydrogen and 88.8% oxygen by mass. What observation might indicate this is a mixture rather than a pure compound?

23. Elements 3 A substance contains 11.2% hydrogen and 88.8% oxygen by mass. What observation might indicate this is a mixture rather than a pure compound? A mixture is a substance made up of different particles, but in a compound every single particle that makes up the substance is exactly the same. Every single particle in the substance would have that same ratio of hydrogen to carbon, if it was a pure substance. If you used a physical process to separate a portion of the substance—sifting, filtering, cutting, etc—and observed a different ratio of hydrogen to carbon you would know it was a mixture.

24. Elements 4 Which number is greater?: (a) The number of noble gas elements? (b) The number of metalloids? (c) The number of elements in period 2? (d) The number of elements that exist as diatomic molecules?

25. Elements 4 Which number is greater?: (a) The number of noble gas elements? (7) (b) The number of metalloids? (7) -> (c) The number of elements in period 2? (8) (d) The number of elements that exist as diatomic molecules? (7)

26. Properties 1 Decide if each of the following is a chemical or physical property: (a) Water boils into steam. (b) Water rusts iron. (c) Water floats on mercury. (d) Water dissolves sugar to make lemonade. (e) Water combines with carbon dioxide to make carbonic acid.

27. Properties 1 Decide if each of the following is a chemical or physical property: (a) Water boils into steam. (Phys) (b) Water rusts iron. (Chem) (c) Water floats on mercury. (Phys) (d) Water dissolves sugar to make lemonade. (Phys) (e) Water combines with carbon dioxide to make carbonic acid. (Chem)

28. Properties 2 For each process below, decide if the energy going into the process is kinetic or potential. Then decide if the energy coming out of the process is kinetic or potential. (a) Sunshine boiling water. (b) Raindrops falling from the clouds. (c) A river filling a lake. (d) A lake overflowing a dam.

29. Properties 2 For each process below, decide if the energy going into the process is kinetic or potential. Then decide if the energy coming out of the process is kinetic or potential. (a) Sunshine boiling water. (KE -> KE) (b) Raindrops falling from the clouds. (PE -> KE) (c) A river filling a lake. (KE -> PE) (d) A lake overflowing a dam. (PE-> KE)

30. Properties 3 Consider the following reaction between carbon monoxide and nitrogen dioxide to yield carbon dioxide and nitrogen monoxide. Is this reaction endothermic or exothermic? Write the chemical equation including the heat of activation. How much heat is consumed or released if 2.50 moles of carbon monoxide are reacted with excess nitrogen dioxide?

31. Properties 3 Consider the following reaction between carbon monoxide and nitrogen dioxide to yield carbon dioxide and nitrogen monoxide. Is this reaction endothermic or exothermic? Write the chemical equation including the heat of activation. How much heat is consumed or released if 2.50 moles of carbon monoxide are reacted with excess nitrogen dioxide? The products have less energy, therefore the reaction is exothermic. 565 kJ are released.

32. Properties 4 A 110.0 g sample of metal is heated to 92.0 ˚C and dropped into 75.0 grams of water at 21.0 ˚C. The final temperature of the water/metal mixture is 24.2 ˚C. What is the specific heat of the metal?

33. Properties 4 A 110.0 g sample of metal is heated to 92.0 ˚C and dropped into 75.0 grams of water at 21.0 ˚C. The final temperature of the water/metal mixture is 24.2 ˚C. What is the specific heat of the metal? (see board)

34. Early Atomic Theory 1 What are the three sub atomic particles? Which is the heaviest and lightest particle, what are the charges on each particle?

35. Early Atomic Theory 1 What are the three sub atomic particles? Which is the heaviest and lightest particle, what are the charges on each particle? The negatively charged electron in the lightest particle. The positively charged proton is 2000 x times heavier than the electron. The neutron has no charge. It’s slightly (~2%) heavier than the proton.

36. Early Atomic Theory 2 Democritus proposed the first model for the atom. Dalton, then Thomson, and then Rutherford each proposed an improvement on that theory. What refinements for the model of an atom did each make?

37. Early Atomic Theory 2 Democritus proposed the first model for the atom. Dalton, then Thomson, and then Rutherford each proposed an improvement on that theory. What refinements for the model of an atom did each make? Democritus proposed that atoms came in different “flavors,” that each element differed from the next by the size and mass of it’s atoms and that these atoms came together to form compounds. Thomson proposed that atoms were composed of sub atomic particles, specifically negatively charged electrons embedded in a positive mass. His model explained the existence of ions. Rutherford proposed that atoms had a massive positively charged nucleus, but otherwise was mostly empty space. His model explained the existence of isotopes and led to the understanding of nuclear reactions.

38. Early Atomic Theory 3 A new element Q has two known isotopes: 80Q and 85Q. A sample of Q is found to have an average mass of 82.5 amu per atom. What is the relative abundance of each isotope? What would be the mass of 1 mole of Q atoms?

39. Early Atomic Theory 3 A new element Q has two known isotopes: 80Q and 85Q. A sample of Q is found to have an average mass of 82.5 amu per atom. What is the relative abundance of each isotope? What would be the mass of 1 mole of Q atoms? The average mass is exactly half way between the two isotopes, the ratio of isotopes must be 1:1. If the average mass is 85.5 amu per atom, the mass of one mole of atoms would be 85.5 grams.

40. Early Atomic Theory 4 Write the isotopic symbol for each of the following neutral particles. (a) A particle with 98 p and 157 n. (b) An atom of element #36 with a mass 82. (c) The result of removing two protons and 1 electron from potassium-39.

41. Early Atomic Theory 4 Write the isotopic symbol for each of the following neutral particles. (a) A particle with 98 p and 157 n. (b) An atom of element #36 with a mass 82. (c) The result of removing two protons and 1 electron from potassium-39.

42. Nomenclature 1 A compound is formed from magnesium and phosphorus. What are the names of the two ions that make up this compound and what is the name of the compound?

43. Nomenclature 1 A compound is formed from magnesium and phosphorus. What are the names of the two ions that make up this compound and what is the name of the compound? Mg2+ is the magnesium ion. P3- is the phosphide ion. Mg3P2 is magnesium phoshide.

44. Nomenclature 2 Many different compounds can be from the same two non-metals. For example N2S5, N2S, N7S4, and NS2 can all be formed from nitrogen and sulfur. What are the names of these four compounds?

45. Nomenclature 2 Many different compounds can be from the same two non-metals. For example N2S5, N2S, N7S4, and NS2 can all be formed from nitrogen and sulfur. What are the names of these four compounds? N2S5 Dinitrogen pentsulfide N2S Dinitrogen monosulfide N7S4 Heptnitrogen tetrasulfide NS2 Nitrogen disulfide

46. Nomenclature 3 Cupric chloride and stannous bromide are two examples of compounds made from transition metals which can have more than one type of charge. What are the stock names for these compounds?

47. Nomenclature 3 Cupric chloride and stannous bromide are two examples of compounds made from transition metals which can have more than one type of charge. What are the stock names for these compounds? Cupric chloride is CuCl2, the stock name for this compound is copper (II) chloride. Stannous bromide has the formula SnBr2, it’s also known as tin (II) bromide.

48. Nomenclature 4 Write the formula for each of the following acids: • Sulfuric Acid • Nitrous Acid • Phosphoric Acid • Chloric Acid • Hydrochloric Acid

49. Nomenclature 4 Write the formula for each of the following acids: • Sulfuric Acid H2SO4 • Nitrous Acid HNO2 • Phosphoric Acid H3PO4 • Chloric Acid HClO3 • Hydrochloric Acid HCl (aq)