General Questions and Answers

omplete the conversion indicated in the image 1 mile 5 280 feet and 60 minutes 1 hour Round up to two decimal places when necessary 5 05 3 mi hr to m

19 List in order of increasing size K Se Cl Nat S

omplete the conver Image 1 meter 3 28 feet and 60 seconds 1 minute Round up to two decimal places when necessary 5 05 answer below ter your response 9 meters second to minu

1 meter 39 4 inches Round to two decimal places when necessary 5 05

Select one It takes about 1 week for a bank to clear your check The electron around a hydrogen atom oscillates 4 3x10 times per second How many electron oscillations happen in the time to clear a check Here are the first two steps in this conversion You will have to complete the conversion to find the final answer a O 12 6 1020 3 81019 2 6 10 20 6 05 105 1 week 7 days 1 week 24 hrs continued 1 day

29 Solve for the molar mass Ag Cr O 2

1 meter 3 28 feet and 60 seconds Round up to two decimal places when necessary 5 05 ter auswer below Enter your response 20 1 minute 3 m to 52 mir

Which of the following would represent a mixture X Y O Z W 8

1 point A sample of Holmium Ho is placed into a crucible weighing 41 889 g empty and the crucible mass with Ho is now 43 539 g The sample is heated in a until it is converted to the oxide product What could be a possible but not exact mass for the crucible plus the oxide product 42 129 g 41 968 g 43 779 g 43 299 g

2 points g What is the mass of 2 04 x 1025 atoms of Cyanide CN O 882 g O 26 0g 53 1g 519g X

Which element would the model below represent Carbon The Atom O Oxygen O Beryllium Magnesium Proton Electron Neutron

How many total electrons are in an F ion O 19 O 10

During the extreme winter months why do car tires need to be readjusted for the decrease in temperature Because the volume of air increases due to the drop in temperature O D Because the volume of air remains the same due to the drop in temperature O Because tire pressure decreases due to the drop in temperature Because tire pressure remains the same due to the drop in temperature

Which of the following would be used to give the most accurate volume of a liquid in the lab Beaker O Graduated cylinder Flask 100 ml AAAAAAAAZZ

2 Determine the number of moles in the following samples 5 19 x 102 g FeCl3 6 02 x1025 g NO

Calculate the percent composition of zinc in zinc phosphide Zn3P2 total mass of element Composition molar mass of compound O 24 76 100

When aluminum sulfate and iron II bromide react what are the products of the reaction O Al2 SO4 3 and FeBr2 O Al2Br3 and Fe SO4 2 O FeSO4 and AlBr3 O Fe3Al2 and Br2SO4

5 A sample of a compound of xenon and fluorine was confined in a bulb with a pressure of 18 torr Hydrogen was added to the bulb until the pressure was 72 torr Passage of an electric spark through the mixture produced Xe and HF After the HF was removed by reaction with solid KOH the final pressure of xenon and unreacted hydrogen in the bulb was 36 torr What is the empirical formula of the xenon fluoride in the original sample Note Xenon fluorides contain only one xenon atom per molecule Also The number of moles of gas is proportional to the partial pressures XeFx H 2 Xe xHF

2 Determine the number of moles in the following samples 5 3 x 10 2 g N 40 000 g MgO

What is the volume shown on the graduated cylinder O24 mL 24 00 mL O24 0 mL 20 40 mL 30 20 10

7 In the following pairs indicate which member would have the higher heat of vaporization and explain why A He or Kr B CH3OH or CH3OCH

What is the molar mass of copper IV nitrate Cu NO3 4 502 g mol O 232 g mol O 309 g mol O 270 g mol

Which of the following correctly describes the formation of ions Nonmetals gain electrons to become anions O Metals gain electrons to become cations O Metals share electrons to become anions Nonmetals lose electrons to become cations

What is the name of the following compound O magnesium chlorate magnesium chlorite O magnesium II chlorate magnesium II chloride Mg CIO3 2

How many neutrons are in an isotope of U 235 143 neutrons 92 neutrons 235 neutrons 146 neutrons

Why does an increase in volume decrease the pressure of a gas O The gas molecules have more kinetic energy that cause it to expand and exert less pressur The gas molecules have less kinetic energy and collide less often O The gas molecules collide less often with more available space

Which of the following substances would contain the most kinetic energy O Hydrogen gas O Boiling water O Solid mercury O Liquid bromine

If I have 21 moles of gas held at a pressure of 78 atm and a temperature of 900 K what is the volume of the gas 19 9 L 22 2 L O No answer text provided 0 15 L

18 What volume of a 0 3300 M solution of sodium hydroxide would be required to titrate 15 00 mL of 0 1500 M oxalic acid

8 Iron has a density of 7 9 g cm What is the mass of a cube of iron with length of one side equal to 55 0 nm

6 Consider the compound Pt en 2Br Br2 and complete parts a c 12 pts a Write the formula for the coordination complex and the counterion Make sure to include charges coordination complex counterion s b For the metal ion in the coordination complex provide the following information Coordination Number Oxidation State Number of d Electrons c What if the en ligands were replaced with NH ligands Predict how the wavelength of light absorbed by the complex would be affected by the switch Fill in the statement below with one of following options greater than less than or equal to The wavelength of light absorbed by Pt en 2Br2 Br2 is light absorbed by Pt NH3 4Br2 Br the wavelength of

3 Predict the impact of temperature and concentration changes on reaction rate rate constant and activation energy 12 pts a Indicate how a decrease in temperature will affect each of the following circle your answers reaction rate decrease increase increase decrease increase decrease rate constant activation energy b Indicate how an increase in reactant concentration will affect each of the following circle your answers reaction rate no change rate constant no change activation energy no change increase increase increase no change no change no change decrease decrease decrease

Which of the following has the largest atomic radius O Neon Ne O Scandium Sc O Lithium Li Barium Ba

thermochemistry a the SI unit of heat as well as all other forms of energy b energy transferred between samples of matter because of a difference in their temperatures calorimeter temperature joule heat specific heat c the amount of energy required to raise the temperature of one gram of a substance by one Celsius degree d the study of the transfers of energy as heat that accompany chemical reactions and physical changes e a measure of the average kinetic energy of the particles in a sample of matter 5 What does AT represent f a device used to measure the energy absorbed or released as heat in a chemical or physical change 2 A quantity called specific heat is used to compare 3 What are the units for specific heat J g C 4 What is the equation for specific heat or K or C 6 Based on the information in table 1 on page 533 which has the highest specific heat water as a gas water as a liquid or water as a solid 7 The energy absorbed as heat during a chemical reaction at constant pressure is represented by 8 True or false An enthalpy change is the amount of energy absorbed by a system as heat during a process at constant temperature

The Carbon family O Noble gases Transition metals Alkali metals are the most reactive family on the periodic table

What element has the following electron configuration 1s 2s 2p63s 3p64s 3d 04p O Calcium O Tin Germanium

The diagram shows the Lewis electron dot structure of element X at ground state Which of these could be the atomic number of element X 05 O 50 13

Calculate the density of a substance with a mass of 78 5 grams and a volume of 5 6 mL O 0 071 g mL O 14 g mL O 440 g mL

8 Consider the oxoacids in parts a b below Circle your answer for each part 4 pts a Which of the following will be a weaker acid H O Br b Which of the following will be a stronger acid H O CI H O Br H O Br 0

What happens during this reaction Cd s NiO s 2H O 1 Cd OH s Ni OH s A Cadmium metal is oxidized B Cadmium metal is reduced C The O atom in H O is reduced The Ni atom in NiO is oxidized

5 When a metal atom becomes a cation loses a a It gains an electron b It becomes a different isotope c Its atomic number changes d Its ionic radius is smaller than its atomic radius 6 Given these elements S Cl Se Br Ar a Which one has the largest radius b Which one is the most reactive valence election c Which one has the highest ionization energy d Which one is the least electronegative 7 The halogens tend to form anions because a They have low first ionization energies b They have low electron affinities c They have high electron affinities d They don t they form cations 8 Unknown element X has four energy levels five valence electrons and is a metalloid What is element X a Si b Ge c Se d As 9 Arrange the following elements in order of increasing effective nuclear charge Bi As P N Sb a Bi Sb As P N b N P As Sb Bi c Bi As P N Sb d N As P Bi Sb 10 An element with a greater effective nuclear atomic radius charge has a n a larger b smaller c undefined d constantly changing 11 Which elements would have the most similar properties a Li Be B c B C N b O S Se d K Ca Rb 12 Which of the following is not true about covalent compounds A they have low melting boiling points B they are formed by the sharing of electrons between atoms C they conduct electricity well D they are usually liquids or gasses at room temperature

Consider a reaction A B AB At which time has this system first reached equilibrium O A B AB before mixing 1 2 3 time C 6 A 1 B 3 D It does not reach equilibrium 5 9

9 How is a thermochemical equation different from other chemical equations 10 Label the following two graphs from pages 536 and 537 Exothermic Reaction Enthalpy Energy as heat is evolved Din Final enthalpy Course of reaction Initial enthalpy AH AH is negative Enthalpy Endothermic Reaction Final enthalpy Energy as heat is absorbed Course of reaction 11 In an endothermic reaction is heat released or absorbed 12 In an exothermic reaction is the change in enthalpy AH positive or negative 13 Which has higher energy in an endothermic reaction the reactants or the products 14 Does the following equation represent an exothermic or an endothermic reaction 2H g O2 g 2H O g AH 483 6 kJ AH is positive AH Initial enthalpy 15 True or false When using thermochemical equations the physical state of the product or reactant involved in the reaction is not an important factor and therefore does not need to be included

20 Standard Reduction Potentials 22 Cu aq 2e Sn aq 2e Fe aq 2e Zn og 2e AP aq 3e 2e Cu x Sn x Fe s Zn s Al x 0 337 V 0 137 V 0 444 V 0 763 V 1 676 V 2 356 V Mg aq Mg s A buried metal tank will not corrode if it is wired to a metal rod that corrodes more easily Which combination protects the tank from corrosion A Mg rod and Sn tank C Fe rod and Al tank B Fe rod and Zn tank D Cu rod and Zn tank 21 The solubility of a salt in water usually increases with increasing temperature because the process is A exothermic so dissolution occurs faster B endothermic so dissolution occurs faster C exothermic so the higher temperature favors dissolution D endothermic so the higher temperatures favors dissolution What is the net ionic equation for the reaction of aqueous solutions of Pb NO and KCI A Pb aq Cl aq PbCl s B Pb aq 2Cl aq PbCl x C Pb NO aq 2KCl aq D 2K aq 2Cl aq Pb aq 2NO aq 2KNO aq PbCl s 2K aq 2NO aq PbCl s 23 Equal volumes of solutions of acids and their sodium salts are mixed to prepare a buffer The solution with pH closest to 5 0 was prepared by mixing A 1 0 x 10 M hydrochloric acid and 0 1 M NaCl B 0 10 M benzoic acid K 6 3 x 10 and 0 10 M sodium benzoate C 0 10 M butyric acid K 1 5 x 10 and 0 10 M sodium butyrate D 0 10 M formic acid K 4 3 x 10 and 0 10 M sodium formate

C 5 9 F 32 F 9 5 C 32 Remember order of operations Questions 1 Convert the following numbers from degrees Fahrenheit F to degrees Celsius C Example 40 F 40 32 8 8 x 5 9 4 4 C a 0 F b 32 0 F freezing point c 70 0 F room temperature d 98 6 F body temperature e 100 0 F f 212 0 F boiling point Convert the following numbers from degrees Celsius to degrees Fahrenheit Example 40 C 40 x 9 5 72 72 32 104 F a 0 C freezing point b 32 0 C c 70 0 C d 98 6 C e 100 0 C boiling point f 212 0 C C C C C C C F F F F F F 2 3 4 6 7 5 16 0 F 8 114 F 9 19 C 99 0 F 24 C 28 C 43 C 80 0 F 10 94 F 11 73 F 12 6 0 C 13 41 C 14 35 0 F 15 117 F 17 25 C 18 52 F 19 17 0 C 20 9 0 C 21 3 0 C 22 44 0 F 23 196 F 24 47 0 F 25 35 0 C 26 26 0 C 27 19 0 C 28 33 0 F 29 93 0 F 30 77 0 F

3 In which set are both compounds soluble in water A magnesium chloride MgCl and octane C H B ethanol CH CH OH and propane CH CH CH C carbon tetrachloride CCI and magnesium chloride MgCl D magnesium chloride MgCl and ethanol CH CH OH FeCl can be prepared from iron and chlorine in two ways 1 Single step route Fe s Cl 8 2 Two step route FeCl s Fe s Cl g FeCl s FeCl s Cl g FeCl s Which is true of the enthalpy changes of these routes 1 A The single step route has an enthalpy change that can be larger or smaller than the two step route depending upon conditions B The single step route will have a smaller enthalpy change than the two step route C The single step route will have a larger enthalpy change than the two step route D The overall enthalpy changes for the two routes are

What volume will 15 2 moles of carbon dioxide CO2 occupy at STP 07 7 L O 340 L 1 5 L 0067L

Chlorine will oxidize I as shown in this equation Cl 21 2CT Use reactivity trends to predict which can be used to prepare Br from Br F Br Cl Br 1 Br I II III A III only C II and III only B I and II only D I II and III

5 Calculate the pH of an aqueous 0 15 M benzoic acid solution A 2 5 B 4 2 Benzoic Acid CH COOH C 5 0 6 Which equation represents this nuclear reaction A H H2He on B H H2He in C H H He in D H H He on K 6 1x10 5 D 6 3 Key proton O neutron

The pH of four different solutions was determined and then small amounts of strong acid 0 01 mol were added consecutively to equal volumes of each Solution 1 2 3 4 initial pH 5 1 5 4 6 2 6 2 pH after adding H first addition second addition 2 1 5 2 3 1 6 0 From these measurements we can conclude that before any acid was added 1 1 5 0 1 8 1 8 A solutions 1 and 3 are buffers but solution 3 has a greater buffer capacity than 1 B solutions 2 and 4 are buffers but solution 2 has a greater buffer capacity than 4 C solutions 3 and 4 are buffers but solution 4 has a greater buffer capacity than 3 D none of the four initial solutions is a buffer