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Chem 1A Study Review
Know your sig-figs! Sig fig rules can be found in Chapter 1, Part 5!
1. Molecules can be described as: a.) mixtures of two or more pure substancesb.) mixtures of two or more elements that have a specific ratio
between componentsc.) two or more atoms chemically joined together d.) heterogeneous mixturese.) homogeneous mixtures
2. Classify each substance as a pure substance or a mixture, if it is a pure substance, classify it as an element or a compound. If it is a mixture, classify it as homogeneous or heterogeneous.
a.)Soda- homo mixb.)Silver metal- elementc.) Propane- compoundd.)Meat soup- hetero mix
3. True or False: A hypothesis must be falsifiable.
4. Which of the following is characteristic of liquids? I. They have a definite volumeII. They have a definite shapeIII. They are compressible IV. They are incompressibleV. They have an indefinite shape
a.) IV onlyb.) I, IIc.) I, II, IVd.) I, III, IVe.) III only
5. True or False: Gases are incompressible, but solids and liquids are compressible. (See Chapter 1, Part 2, Slide 6)
*insert test taking strategy! * ;)
6. Using your understanding of chemical and physical changes, classify each of the following as a chemical change or a physical change:
Chem 1A Study Review
Know your sig-figs! Sig fig rules can be found in Chapter 1, Part 5!
(I) Adding ethylene glycol (antifreeze) to water in your radiator causes the ethylene glycol to dissolve in water. physical(II) Burning coal and producing CO2 and H2O as products chemical(III) Sublimation of dry ice (CO2) physical(IV) Your catalytic converter in your car reduces pollution you emit when you drive by converting NO2 (a brown, foul gas) to produce O2 and N2 (colorless, nontoxic gases) chemical
a. (I) and (III) are physical change, and (II) and (IV) are chemical change
b. (I) and (II) are physical change, and (III) and (IV) are chemical change
c. (I) and (IV) are physical change, and (II) and (III) are chemical change
d. (II) and (III) are physical change, and (I) and (IV) are chemical change
e. (II) and (IV) are physical change, and (I) and (III) are chemical change
7. Identify the SI base unit of mass and temperature, respectively: (See Chapter 1, Part 4, Slide 3)
a. Grams and Celsius b. Kilograms and Kelvinc. Grams and Kelvind. Pounds and Fahrenheit
8. Which of the following is the lowest temperature?a. 48°C b. 64°F c. 313 K d. All of these temperatures are all equal
9. Which of the following describes a nonmetal?a. are only solidsb. found in the left side of the periodic tablec. conducts electricityd. are poor conductors of heate. tend to lose electrons
Chem 1A Study Review
Know your sig-figs! Sig fig rules can be found in Chapter 1, Part 5!
10. Identify the longest length. (1 ft= 30.48 cm; 1 inch =2.54 cm (exactly); 1 yd= 3 ft, 1 m =100 cm; 1 m = 1.094 yd; 1 km = 0.6214 mile)
a. 3.05 ftb. 38.0 inc. 1.04 yd d. 1.05 m e. 86.87 cm
11. Convert 1.76 miles to meters. 2.83 x 10^3m
12. Use exponential notation to express 4.22 mg in grams.
13. An acetaminophen suspension for infants contains 80 mg/0.80 mL suspension. The recommended dose is 15 mg/kg body weight. How many mL of this suspension should be given to an infant weighing 14 lb? (Assume two significant figures.) 0.95 mL
14 lb x 1/2.2 x 15/1 x 0.80/ 80
14. What is the difference between precision and aCCuracy?
15. What answer should be reported, with the correct number of significant figures, for the following calculation?
(433.621 - 333.9) x 11.900a. 1.19 x 10^3b. 1.187 x 10^3c. 1.1867 x 10^3d. 1.18670 x 10^3e. 1.1866799 x 10^3
16. The diameter of an atom is approximately 1 ×10^-10 m. What is the diameter in decimeters?
a. 1 ×10^-24 dmb. 1 ×10^-21 dmc. 1 ×10^-9 dmd. 1 ×10^-6 dm
17. Identify a cation.
Chem 1A Study Review
Know your sig-figs! Sig fig rules can be found in Chapter 1, Part 5!
a. an atom that has lost an electronb. an atom that has gained an electron c. an atom that has lost a protond. an atom that has gained a proton and an electron e. an atom that has lost a neutron and an electron
18. An atom that has an atomic number of 34 and a mass number of 76 is an isotope of an atom that has:
A) an atomic number of 32 and a mass number of 76 B) an atomic number of 34 and a mass number of 80C) 42 neutrons and 34 protonsD) 42 protons and 34 neutronsE) 42 electrons and 34 neutrons
19. What mass (in kg) does 5.95 moles of titanium (Ti) have? 0.285 kg
20. Determine the number of protons, number of electron, and neutrons for:
31
15, 18, 16
21. Which of the following contains the MOST atoms?
a. 4.0 g Lib. 4.0 g Nac. 4.0 g Rbd. 4.0 g of Ke. 4.0 g Ca
22. Silver has an atomic mass of 107.868 amu. The Ag-109 isotope (108.905 amu) is 48.16%. What is the amu of the other isotope? 106.9 amu
107.868 = (108.905 x 0.4816) + (amu x 0.5184)
Chem 1A Study Review
Know your sig-figs! Sig fig rules can be found in Chapter 1, Part 5!
23. True or False: Covalently bonded compounds are also called molecular compounds.
24. True or False: Covalent bonds occur between two or more metals. The two atoms share electrons between them.
25. What is the difference between polar covalent bonds and nonpolar covalent bonds?
26. How many copper atoms are in a penny weighing 3.10 g?
2.94 x 10^22 atoms Cu
27. Give a possible molecular formula for the empirical formula: C2H5N
28. Write the name of the ionic compound CuF2 Copper (II) fluoride
29. Write the name of the compound Ag2SO4 Silver sulfate
How many phosphorus atoms are contained in 158 kg of phosphorus? 3.07 x 10^26 atoms P
30. State the formula for tetraphosphorous decasulfide
31. Name the following molecular compounds:a. As2S3 diarsenic trisulfideb. SF6 sulfur hexafluoride
32. Name the following: a. HClb. HIc. HFd. H2SO4e. HClO2
Chem 1A Study Review
Know your sig-figs! Sig fig rules can be found in Chapter 1, Part 5!
33. Write the formula for each acid: a. Phosphoric acid H3PO4b. Hydrocyanic acid HCNc. Nitrous acid HNO2
34. Find the mass percent of Cl in Freon-112 (C2Cl4F2) 69.58%Mass % Cl= (molar mass Cl)(moles of Cl)/ molar mass C2Cl4F2 x 100
35. Upon combustion, a compound containing only carbon and hydrogen produces 3.66 g CO2 and 1.802 g H2O. Find the empirical formula of the compound.
36. How many significant figures are in each of the following: a. 0.04450 m 4 SF
b. 5.0003 km 5 SFc. 1.000 ×10^5 s 4 SF d. 0.00002 mm 1 SFe. 10,000 m ambiguous
37. According to the U.S. Department of Energy, the world burned 3.6 x 10^10 barrels of petroleum in 2017, the equivalent to ~4.0 x 10^15g of
Chem 1A Study Review
Know your sig-figs! Sig fig rules can be found in Chapter 1, Part 5!
gasoline. By using the combustion of 4.0 x 10^15 g octane as representative reaction, calculate the mass of CO2 produced.
• The equation for the reaction of octane(C8H18) is:𝟐𝐶8𝐻18𝑙+𝟐𝟓𝑂2𝑔→𝟏𝟔𝐶𝑂2𝑔+𝟏𝟖𝐻2𝑂(𝑔)
or x 10^13 kg CO2
38. How many moles of oxygen are formed when 58.6 g of KNO3 decomposes according to the following reaction? The molar mass of KNO3 is 101.102 g/mol .
4 KNO3(s) → 2 K2O(s) + 2 N2(g) + 5 O2(g)0.725 mol O2
39. How many moles of Si3N4 can be made from 1.20 moles of Si and 1.00 moles of N2 in the following reaction?
Chem 1A Study Review
Know your sig-figs! Sig fig rules can be found in Chapter 1, Part 5!
40. 64.0 g of methanol, CH3OH, were expected to be produced through the reaction𝐶𝑂𝑔+2𝐻2𝑔→𝐶𝐻3𝑂𝐻(𝑙). One student got 56.0 g of methanol, for that reaction in the laboratory. What is the %yield of methanol?
87.5 %
41. Hematite, Fe2O3,is important ore of iron.(An ore is a natural substance from which the metal can be profitably obtained.) The free metal is obtained by reacting hematite with carbon monoxide, CO, in a blast furnace. Carbon dioxide is formed in the furnace by partial combustion of carbon. The reactions is: 𝐹𝑒2O3 (s) + 3𝐶𝑂 (g)→ 2𝐹𝑒 (s) + 3𝐶𝑂2 (g). How many kilograms of iron can be produced from 1.00 Kg Fe2O3?
Chem 1A Study Review
Know your sig-figs! Sig fig rules can be found in Chapter 1, Part 5!
42. A 12.39 g sample of phosphorus reacts with 11.31 g of chlorine to form only phosphorus trichloride (PCl3). If it is the only product, what mass (g) of PCl3 is formed? A possibly useful molar mass is P = 30.974 g/mol; PCl3= 137.324 g/mol; Cl = 35.45 g/mol.
43. Identify a characteristic that is NOT true of halogens.a. halogens react with hydrogen b. halogens react with other halogensc. halogens are metalloids
Chem 1A Study Review
Know your sig-figs! Sig fig rules can be found in Chapter 1, Part 5!
d. halogens react with metalse. halogens form covalent bonds
44. Identify the states of the halogens at room temperature. a. Fluorine, chlorine, bromine, and iodine are gases.b. Fluorine, chlorine, and bromine are gases, and iodine is a solid.c. Fluorine and iodine are liquids, chlorine and bromine are solids.d. Fluorine is a gas, chlorine and bromine are l liquids, and iodine
is a solids.e. Fluorine and chlorine are gases, bromine is a liquid, and iodine
is a solid.
45. When dissolved in water, NaOH behaves as a. an acid that forms Na+ and OH- ions.b. an acid that forms NaO and H+ ions.c. a base that forms Na+ and OH- ions.d. a base that forms NaO-and H+ions.
46. How many moles of NaCl are required to make 250. mL of a 3.00M solution?
a. 0.750 moles
47. Determine the molarity of a solution formed by dissolving 468. mg of MgI2in enough water to yield 50.0 mL of solution. A possibly useful molar mass is MgI2= 278.105 g/mol. 0.0337 M
48. How many dietary (nutritional) calories are equivalent to 1.75 10^3 kJ?kJ to J to cal to Cal
49. Calculate E of a system that absorbs 35 J of heat and does 44 J of work on the surroundings.
a. -9 J, change in E= q (+) + w (-)
50. Reacting 50 mL of H2(g) with 50 mL of C2H4(g) produces 50 mL of C2H6(g) at 1.5 atm. If the reaction produces 3.1 x 102J of heat and the
Chem 1A Study Review
Know your sig-figs! Sig fig rules can be found in Chapter 1, Part 5!
decrease in volume requires the surroundings do 7.6 J of work on the gases, what is the change in internal energy of the gases?
a. -302.4 J
51. Calculate the kinetic energy in kJ of a 150 g baseball moving at a speed of 39. m/s (87 mph).
114.075 J to 0.11 kJ
52. Thermochemistry studies the relationship between ________ (energy/chemical) changes and ________(energy/chemical) processes.
53. How much energy is evolved during the reaction of 55.2 g of Al, according to the reaction below?
Assume that there is excess Fe2O3. Fe2O3(s) + 2 Al(s) → Al2O3(s) + 2 Fe(s)ΔH°rxn= -852 kJ
54. How much heat is absorbed by a copper penny with mass 3.10 g whose temperature rises from −8.0 °C to 37.0 °C?
53.7 J, Cs=0.385 J/ g x C
54. When 1.010 g of sugar (MM=342.3 g/mol) is burned in a bomb calorimeter, the temperature rises from 24.92 °C to 28.33 °C. If C cal= 4.90 kJ/°C, find E for burning 1 mole. Qcal= Ccal x change in T , -16.709 kJ
Chem 1A Study Review
Know your sig-figs! Sig fig rules can be found in Chapter 1, Part 5!
55. Characterize each change as endothermic or exothermic and give the sign of ΔH.
a. Vaporization H2O(l) →H2O(g) endo H >0b. Condensation H2O(g) →H2O(l) exo H<0c. CH4(g) + 2O2(g) →CO2(g) + 2H2O(g) exo H<0
56. The following reaction C(s) and H2O(g) is an industrially important method of generating hydrogen gas:
C𝑠+H2O(𝑔)→CO𝑔+H2(𝑔) ∆𝐻𝑟𝑥𝑛= And we know the following reactions that have known H’s :
C𝑠+O2(𝑔)→CO2(𝑔) ∆𝐻𝑟𝑥𝑛=-393.5 kJ2CO𝑠+O2(𝑔)→2CO2(𝑔) ∆𝐻𝑟𝑥𝑛=-566.0 kJ 2H2(𝑔)+O2(𝑔)→2H2O(𝑔) ∆𝐻𝑟𝑥𝑛=-483.6 kJ
+131.3 kJ
57. If a balloon is inflated from 0.100 L to 1.85 L against an external pressure of 1.00 atm, how much work is done in Joules?
W= -P delta V, 1 L*atm= 101.3 J, 177 J
58. What is the molarity of a solution containing 25.5 g KBr dissolved in enough water to make 1.75 L solution? 0.122 M
59. To what volume (in mL) should you dilute 100.0 mL of a 5.00 M CaCl2 solution to obtain a 0.750 M CaCl2 solution?667 mL
ONE MORE PAGE!!! RESOURCES!!!
Disclaimer: No copyright infringement intended. The following practice problems were taken from Dr. Marzal’s course resources as well as Nivaldo J. Tro, “Chemistry, A Molecular Approach”. The links where the included images were found are directly below the images. These problems are only meant to supplement your review. This does not cover everything you may encounter on the final as I don’t know exactly what
Chem 1A Study Review
Know your sig-figs! Sig fig rules can be found in Chapter 1, Part 5!
will be on your final. Although this study guide has been thoroughly reviewed, mistakes happen, and I can’t guarantee everything in this study guide is perfect.
PLEASE don’t use this as your only study resource for the final!
Photo credit: https://www.pinterest.com/pin/271412315027967029/
Chem 1A Study Review
Know your sig-figs! Sig fig rules can be found in Chapter 1, Part 5!
Photo credit: https://www.slideserve.com/oke/significant-figures-rules
