HONORS & CP CHEMISTRY MID TERM EXAM REVIEW gugs 1 1. How many atoms of hydrogen are present in 3 moles of acetic acid? 2 1. How many atoms of hydrogen are present in 3 moles of acetic acid? 3 mol HAc(4 moles H/1 mol HAc) = 12 mol H atoms 12 mol H atoms (6.02 X 1023atoms/1mol) = 7.22 X 1024atoms gugs 3 2. What is the molecular formula of butane? gugs 4 2. What is the molecular formula of butane? C4H10 gugs 5 3. How many moles of carbon are present in 2 moles of butane? gugs 6 3. How many moles of carbon is present in 2 moles of butane? 2 mol butane (4 mol C/1 mol butane) = 8 mol C gugs 7 4. What is the percent composition of ethanol? gugs 8 4. What is the percent composition of ethanol? First find GFM: 2C = 24.0 6H = 6.0 1O = 16.00 46 g/mol gugs 9 4. - continued What is the percent composition of ethanol? %C = 24.0/46 (100)= 52% %H = 6.0/46 (100) =13% %O = 16.00/46(100) = 35% gugs 10 5. Classify the reactions shown below gugs 11 5.Classify the reactions shown below Decomposition gugs 12 5. Classify the reactions shown below Decomposition Double replacement gugs 13 5. Classify the reactions shown below Decomposition Double replacement Synthesis gugs 14 5. Classify the reactions shown below Decomposition Double replacement Synthesis Single replacement gugs 15 6. What number should be written in front of Na to balance the equation Na + Cl2 NaCl ? gugs 16 6. What number should be written in front of Na to balance the equation Na + Cl2 NaCl ? 2 gugs 17 7. What number should be written in front of Fe in order to balance Fe + O2 Fe2O3? gugs 18 7. What number should be written in front of Fe in order to balance Fe + O2 Fe2O3? 4 gugs 19 8.Measure the object with the ruler to the correct number of significant figures. gugs 20 8. Measure the object with the ruler to the correct number of significant figures. 11.65 cm gugs 21 9. Classify each as accurate &/ or precise gugs 22 9. Classify each as accurate &/ or precise gugs 23 10. What symbol expresses uncertainty in a measurement? 24 10. What symbol expresses uncertainty in a measurement? +/- 25 11. Name the compound S3O6 26 11. Name the compound S3O6 Trisulfur hexoxide 27 12. What is the formula for the compound that is formed by magnesium and hydroxide ions? 28 12. What is the formula for the compound that is formed by magnesium and hydroxide ions? Mg(OH)2 29 13. What is the formula for the compound that will form between calcium and phosphate ions? 30 13. What is the formula for the compound that will form between calcium and phosphate ions? Ca3(PO4)2 31 14. What is the correct formula for barium oxide? 32 14. What is the correct formula for barium oxide? BaO 33 15. What is the volume of a mole of gas at STP? 34 15. What is the volume of a mole of gas at STP? 22.4 L 35 16. In a chemical reaction, the total mass of the products compared to the total mass of the reactants is 36 16. In a chemical reaction, the total mass of the products compared to the total mass of the reactants is always the same 37 17. Calculate the number of atoms in 1.40 mol of Ag. 38 17. Calculate the number of atoms in 1.40 mol of Ag. 1.40 mol (6.02 X 10 23 atoms) 1 mol = 8.43 X 10 23 atoms 39 18. Calculate the number of liters of gas in 1.47 mols at STP 40 18. Calculate the number of liters of gas in 1.47 mols at STP 1.47 mol (22.4 L) 1 mol = 32.9 L 41 19. In the formula Ca3(PO4)2, the total number of oxygen atoms is 42 19. In the formula Ca3(PO4)2, the total number of oxygen atoms is 2 X 4 = 8 oxygen atoms 43 20. In the formula 3 Mg(NO3)2, the total number of oxygen atoms is 44 20. In the formula 3 Mg(NO3)2, the total number of oxygen atoms is 3 (3 X 2) = 18 oxygen atoms 45 21. In the formula 3 Mg(NO3)2, the total number of atoms is 46 21. In the formula 3 Mg(NO3)2, the total number of atoms is 3 (3 X 2) = 18 oxygen atoms 3X2= 6 N atoms + 3 Mg atoms = 27 total atoms 47 22. In the expression 3Mg(NO3)2, the number 2 is known as 48 22. In the expression 3Mg(NO3)2, the number 2 is known as the ______. subscript 49 23. In the expression 6 Ca3(PO4)2, the 6 is known as the 50 23. In the expression 6 Ca3(PO4)2, the 6 is known as the _____. coefficient 51 24. What is the name of the Law that directs us to balance equations? 52 24. What is the name of the Law that directs us to balance equations? The Law of Conservation of Matter 53 25. When oxygen is available, nitrogen dioxide is produced from the burning of nitrogen. Write the word equation for this reaction. 54 25. When oxygen is available, nitrogen dioxide is produced from the burning of nitrogen. Write the word equation for this reaction. nitrogen + oxygen nitrogen dioxide 55 26. Give two examples of a chemical change. 56 26. Give two examples of a chemical change. Souring milk, burning anything, cooking, decaying leaves… 57 27. Classify each of the following reactions: 2 Mg + O2 2MgO CH4 + O2 CO2 + 2 H2O AgNO3 + NaCl NaNO3 + AgCl H2 O H2 + O 2 AgCl + Cu CuCl + Ag 58 27. Classify each of the following reactions: 2 Mg + O2 MgO synthesis CH4 + O2 CO2 + 2 H2O AgNO3 + NaCl NaNO3 + AgCl H2 O H2 + O 2 AgCl + Cu CuCl + Ag 59 27. Classify each of the following reactions: 2 Mg + O2 MgO synthesis CH4 + O2 CO2 + 2 H2O combustion AgNO3 + NaCl NaNO3 + AgCl H2 O H2 + O 2 AgCl + Cu CuCl + Ag 60 27. Classify each of the following reactions: 2 Mg + O2 MgO synthesis CH4 + O2 CO2 + 2 H2O combustion AgNO3 + NaCl NaNO3 + AgCl double replacement H2O H2 + O 2 AgCl + Cu CuCl + Ag 61 27. Classify each of the following reactions: 2 Mg + O2 MgO synthesis CH4 + O2 CO2 + 2 H2O combustion AgNO3 + NaCl NaNO3 + AgCl double replacement H2O H2 + O2 decomposition AgCl + Cu CuCl + Ag single replacement 62 27. Classify each of the following reactions: 2 Mg + O2 MgO synthesis CH4 + O2 CO2 + 2 H2O combustion AgNO3 + NaCl NaNO3 + AgCl double replacement H2O H2 + O 2 AgCl + Cu CuCl + Ag single replacement 63 27. Classify each of the following reactions: 2 Mg + O2 MgO synthesis CH4 + O2 CO2 + 2 H2O combustion AgNO3 + NaCl NaNO3 + AgCl double replacement H2O H2 + O2 decomposition AgCl + Cu CuCl + Ag single replacement 64 28. Balance each of the following equations a. b. c. d. NaCl Na + Cl2 S + Cl2 SCl2 K + AgCl Ag + KCl Ca(OH)2 + HCl H2O + CaCl2 65 28. Balance each of the following equations a. b. c. d. 2 NaCl 2 Na + Cl2 S + Cl2 SCl2 K + AgCl Ag + KCl Ca(OH)2 + 2 HCl 2 H2O + CaCl2 66 29. Use the experiment shown in the figure to answer the questions a. A gas was given off, collected in a test tube, and then tested with a burning splint. A “pop/chirp” was heard. What was the gas? 67 29. Use the experiment shown in the figure to answer the questions a. A gas was given off, collected in a test tube, and then tested with a burning splint. A “pop/chirp” was heard. What was the gas? hydrogen 68 29. Use the experiment shown in the figure to answer the questions b. The substances Mg metal and dilute HNO3, are called --? 69 29. Use the experiment shown in the figure to answer the questions b. The substances Mg metal and dilute HNO3, are called --? reactants 70 29. Use the experiment shown in the figure to answer the questions c. Write the correct balanced equation for the experiment 71 29. Use the experiment shown in the figure to answer the questions c. Write the correct balanced equation for the experiment Mg + 2HNO3 H2 + Mg(NO3)2 72