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Practice Final (Print) Name last First Signature

Introduction to General Chemistry, Ch152 Practice Final Exam 1 Who was first responsible for presenting the planetary model of the atom ? a) Dalton b) Millikan c) Rutherford d) Bohr 2 A ruler is marked in .1 cm intervals. What is the uncertainty associated with the ruler? a) 1 cm b) 0.1 cm c) 0.01 cm d) 0.001 cm 3 "VSEPR" is an example of a: a) law b) hypothesis c) experiment d) theory 4 The process in which liquid turns to solid is called: a) sublimation b) melting c) deposition d) freezing 5 Water evaporating involves what type of change ? a) intensive b) physical c) chemical d) personality 6 Which one of the following measurements contains the fewest number of significant figures? a) 0.01003 mm b) 100360 mL c) 1.00 • 10-4 g d) 1300 kg 7 Which has two valence electrons ? a) C b) N c) Ne d) Ca 8 In which of the following is the metric unit paired with an incorrect abbreviation? a) km and kilometer b) milliliter and mL c) Kelvin and K d) microgram and mg 9 In the number 1234.5689, which digit is to the hundredth of a place? a) 8 b) 6 c) 5 d) 2 10 If 20 drops equal 1.00 ml, how fast should a nurse adjust the drop rate of an intravenous (IV) bag to deliver 0.900 L in a

10-hr period. Calculate the drop rate in drops per min. a) 69 drops/min b) 42 drops/min c) 30 drops/min d) none 11 Consider several neutral atoms in which the symbol of the elements is represented by X: 8

1 6X 91 7X 1 0

1 8X 81 7X 7

1 5X How many of these atoms have eight neutrons ?

a) 2 b) 3 c) 4 d) can not be determined

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Please refer to the following diagram for the next series of questions.

12 Which family of elements has the lowest ionization energy ? a) q b) r c) z d) y 13 Which arrows correspond to decreasing non-metallic character ? a) 2 & 3 b) 1 & 4 c) 3 & 1 d) 4 & 2 14 Consider the Bohr diagram for two reactants. What is the class

of compound from the resulting product? a) covalent b) ionic c) polar covalent d) metallic

Reactant 1 Reactant 2

+ 15 Which has the largest energy ? a) radio-waves b) microwave c) infrared d) ultraviolet light 16 Electron always have different set of quantum numbers (different address) because of: a) Aufbau b) Pauli exclusion c) Uncertainty principle d) Hund's rule 17 Which is the electron box diagram for the unstable aluminum anion Al4- .

18 Which compound has the smallest molar mass ? a) H2Te b) CS2 c) CH2Br2 d) PCl3 19 Which compound is polar ? a) CH4 b) Br2 c) O3 d) none are polar 20 Which set has compounds that have the same electronic geometry (AEn) ? a) O3 and N3 - b) CH4 and CF4 c) SO2 and CO2 d) H2O and CO2

21 How many grams of H2 are formed from the decomposition of 340 g NH3: 2NH3(g) g N2(g) + 3H2(g) a) 25 g b) 30 g c) 280 g d) 60 g

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22 The following reaction: C6H12O6 + 6O2 g 6CO2 + 6H2O may be classified as a a) single displacement reactions b) combination reaction c) combustion d) neutralization reaction 23 Which postulate from the kinetic molecular theory describes Boyle’s Law ? a) Gases are in random motion and are separated by large distances. b) kinetic energy of gas is directly proportional to the temperature c) Volume of the gas is negligible d) As the pressure increase, the volume decreases. 24 How much would 9.56•1021 molecules of nitric acid weigh ? (HNO3 : MW = 63.0 g/mol Nav: 6.02•1023)

a) 1.00 g b) 6.02•1023 g c) 1.00•10-23 g d) 63.0 g 25 In the reaction : 2NaOH + H2SO4 g Na2SO4 + 2H2O How many moles of water is formed when 2.0 moles of

H2SO4 reacts with excess NaOH ? a) 1 b) 2 c) 4 d) 6 26 Which is an example of a Lewis formula ?

a) C2H5 b) c) Sn2O4 d) sodium bromide 27 Which arrangement is in order of increasing electronegativity ? a) Cl, H, Br, C b) B, F, P, O c) Al, K, N, F d) Sr, Sc, Si, Cl 28 Which chemical has seven bonds ? a) C2H4 b) C2H2 c) C2H6 d) C3H 29 What information about a chemical formula will always lead you to the correct type (I, II or III) of compound. a) Identity of metal or the first element in the compound. b) the number of valence electrons. c) total electrons in the anion. d) the family of the metal. 30 What is “x” in the formula (NH4)x CO3 ? a) 1 b) 2 c) 3 d) 4 31 Which of the following has a "+2" cation in its formula ? a) CO b) Pb(SO4)2 c) (NH4)3N d) SnO 32 Indicate the mass action expression for the following reaction:

2X(g) + Y (g) D 3W(g) + V(g)

a) W[ ]3 V[ ]X[ ]2 Y[ ] b)

3W[ ] V[ ]2X[ ] Y[ ]

c) X[ ]2 Y[ ]W[ ]3 V[ ]

d) X[ ]2 Y[ ] W[ ]3 V[ ]

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33 What is the percentage yield if the theoretical yield in a reaction is 60.4 grams but only 51.7 grams was actually recovered

? a) 1.17 % b) 85.6 % c) 8.56 % d) 117 % 34 Which among the following will turn blue litmus paper to a red color ? a) carbonic acid b) table salt c) NaOH d) ammonia 35 The solubility of a gas increases with: a) increase temp b) increase pressure c) increase agitation d) all of these 36 An anesthesiologist administers a gas at 20° C to a patient whose body is 37° C. What is the change in volume (L) of a

1.20 L sample of gas as it goes from room temperature to body temperature? a) 1.27 L b) 0.788 L c) 2.22 L d) 1.20 L 37 Which reaction coordinate diagram illustrates the fastest exothermic reaction?

a) b) c) d) 38 Consider the following diagram to the right

From this reaction coordinate diagram, the equilibrium constant

can be determined to be: a) Keq < 1 b) Keq = 1 c) Keq > 1 d) Keq cannot be determined.

39 Which is the strongest acid below ? a) HF, Ka = 6.8•10-4 b) CH3COOH, Ka = 1.8•10-5

c) NH4+, Ka = 5.68•10-10 d) H3PO4, Ka = 3.0•10-2 40 The bond angle between for H-C-H in methane is a) 180° b) 109.5° c) 120° d) 90°

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A + B ! C

B

A

C

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Show All work to receive full credit (Keep your answers short and concise) 41 For the following, write the type (Type I, II or III) of compound, chemical formula, chemical name.

Elements or ions in formula Type Chemical Formula Chemical Name

i copper(II) & hydroxide

ii potassium & one sulfur

iv One nitrogen and five oxygen

vi H & bisulfate ion

42 Briefly explain in detail by pictures and words the difference between the following: i) accuracy and precision ii) pure substance and a homogenous mixture iii) polarity and polarizability iv) What makes water so unique compared to other simple light-weight molecules? 43 Choose which chemical from the list has the highest property, then explain or show why. i) boiling point: a) Rn, b) Xe, c) H

ii) molar mass: a) CO, b) O2, c) NO

iii) total valence electron: a) H2O+, b) CO, c) BH3

iv) largest bond angle around the central atom: a) H2S, b) SiS2, c) SeO2

v) Highest hydroxide ion [OH-] concentration: a) 1.5•10-6 M KOH, b) 1.5•10-5 M HNO3, c) pH = 8.5

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44 This semester I have tried to convince you that the valance electrons in atoms are responsible for chemistry. i) Discuss the present model of the atom and explain where the valence electrons are located in the atom and its

importance.. ii) Explain the relationship between the valence electrons of an atom and atomic radius, ionization potential (energy) and

electron affinity. iii) Explain how the valence electrons from different atoms interact to form atomic bonds. What are the different types? iv) Explain how the valence electron rearrange themselves to dictate the shape of molecules and how these shape influence

the polarity of the molecule. 45 For the following unbalance equation, answer the following questions: __ Fe2S3 (s) + __ CS (g) → __ Fe (s) + __ CS2 (g)

a) How many moles of iron(III) sulfide is consumed if 33 moles of carbon monosulfide b) How many grams of iron (Fe) is produced if 18 moles of carbon disulfide is consumed? c) What mass (g) of CS2 is produce if 132.0 g of CS is consumed in the above reaction?

d) How many molecules of CS is generated from 44 grams of CS2 ?