General Questions and Answers
Physical Chemistry
GeneralThe technetium 99 nuclide radioactively decays by beta emission Write a balanced nuclear chemical equation that describes this process 0 0 80 Y
Physical Chemistry
General3 The empirical formula of a molecule is C HO7 and the molecular mass is 237 What is the molecular formula for the compound
Physical Chemistry
GeneralWhat type of amino acid is tyrosine O a Polar neutral O b Acidic c Nonpolar neutral Od Basic
Physical Chemistry
General1 point What volume of carbon dioxide gas is produced if 8 00 mol gaseous propane are combusted Round answers to 2 decimal places only numerals
Physical Chemistry
GeneralEven a compound has the following mass percent of elements Mg 23 29 S 30 72 and O 45 99 Given the molar mass in g m 2 06 and O 16 00
Physical Chemistry
GeneralNaOH NaCl NaBr Nal Na2SO4 Na CO3 Na C2O4 Mg NO3 2 Ca NO3 2 Sr NO3 2 Ba NO3 2 What is the electron configuration of lead re laboratory Assignment Show works for all calculations Give the names and symbols of the alkaline earth metals that you will encounter in this experiment Magnesium Answer each of the following questions in complete sentence a What is the general electron configuration of the alkaline earth metals Pb NO3 2
Physical Chemistry
GeneralBased on the properties of the compounds in the interactive predict whether the given compounds behave as electrolytes or as nonelectrolytes Electrolyte Nonelectrolyte
Physical Chemistry
General12 For a given chemical reaction involving only gasses at equilibrium if AG 0 will there be more product formed or more reactant Justify your answer using one or more equations ran
Physical Chemistry
GeneralHow much water is needed to add to 34 1 mL of 5 86 M KNO3 aqueous solution to make a 2 22 M solution Answer to 1 decimal place Type your answer
Physical Chemistry
GeneralExperiment 8 Electron Configurations 2 Given the quantum number n 4 a How many subshells is in this shell Write all the quantum numbers 1 associated with the subshells b What is the maximum electron occupancy in this shell Lab Repo c For each of the subshells write the name of the subshells associate with each quantum number 1 number of orbitals in the subshell and the quantum numbers m of the orbitals 3 Write all the possible sets of four quantum numbers for the subshell 3p
Physical Chemistry
General10 Give the mathematical definition of chemical potential Explain why it is called a poten Include at least one drawing Y
Physical Chemistry
Generalc Compare the formulas of the oxides formed by the alkaline earth metals with those of lead 3 Give general formulas for the following compounds with alkaline earth metals or lead use the symbol M to represent the metal a A sulfate b A chloride c A carbonate d An iodide e A bromide f An oxalate g A hydroxide h A nitrate i A chromate 4 What general method will be used to examine qualitative solubility in this experiment
Physical Chemistry
GeneralWhy is Gibb s free energy usually more useful to chemists than Helmholtz energy
Physical Chemistry
Generala Derive the following expression 05 Px av T h How does the molar entrony change with increasing volume
Physical Chemistry
GeneralSuppose a fluorine 17 nuclide transforms into an oxygen 17 nuclide by absorbing an electron and emitting a gamma ray Complete the nuclear chemical equation below so that it describes this nuclear reaction 0 30 v Y C
Physical Chemistry
GeneralA chemist mixes 500 milliliters of a solution that is 62 acid with 125 milliliters of a solution that is 27 acid Answer the questions below Do not do any rounding a How many milliliters of acid are in the resulting mixture milliliters b What percentage of the resulting mixture is acid
Physical Chemistry
GeneralWhich of the following molecules can form hydrogen bonds OCH4 and NH 3 O H O OH O and NH3 O CH4 O NH3
Physical Chemistry
General2 moles of H O contains O 1 2 x 1024 O 2 41 x 1024 2 41 1023 O6 02 x 1024 04 O atoms
Physical Chemistry
GeneralModels help scientists visualize concepts Five models are given below Model 1 Model 2 Models 4 and 5 Model 3 Model 4 Model 5 Which models would represent very reactive nonmetals Models 1 2 and 3 Models 1 3 and 4 Models 1 and 3 1s 2s 2p 3s 3p oxidation number of 1 1s 2s 2p 3s
Physical Chemistry
Generallonic bonding is expected in which of these compounds O Cao O 0 O H O H O O H O2
Physical Chemistry
Generalwwwwww wwwwww What is the molarity of a solution containing 400g CuSO4 in 4 00L of solution this is a M n V NOT CIV1 C2V2 wwwwwww
Physical Chemistry
GeneralG final level of 200mL STEP 1 Convert 50g to mol of NaCl How many moles are there Your answer on of a solution when water is added to 50g of Naci to STEP 2 Convert mL to L of solution How many L of solution Your answer 2 PO 2 po STEP 3 Solve What is the molar concentration of the solution described abol include units
Physical Chemistry
GeneralTwo students collect data on three unknown samples in the lab Their data is presented in the table below Number of protons Number of neutrons Number of electrons Appearance Reacts with acid Mass Number Element X 19 21 19 solid dull gray yes 40 Element Y 20 20 20 solid dull light gray yes 40 Element Z unknown unknown New data determines that Element Z has 20 protons 19 solid dull gray yes 40 Student 1 turned in his lab sheet stating that all three samples must be the same element because their appearance reactivity with acid and mass number were all the same Student 2 disagreed and wrote that Element X and Z were the same while Element Y was different She argued that the similar appearance identical number of electrons and identical mass number means that Element X and Z are the same element Which of the following would be most likely to disprove the second student s argument
Physical Chemistry
GeneralCovalent bonding is O oppositely charged ions held together by strong electrical attractions Osimilarly charged ions held together by strong electrical attractions O sharing of electrons by atoms O metal bonding with metal Ohydrogen bonding
Physical Chemistry
GeneralA red hot iron nail is immersed in a large bucket of water Although the nail cools down sufficiently to be held bare handed the temperature c the water barely increases Which properties keep the water temperature from changing much DD O water s high heat conductivity water s high specific heat capacity the iron nail s high heat conductivity the large mass of water the iron nail s high specific heat capacity
Physical Chemistry
GeneralAqueous sulfuric acid H SO reacts with solid sodium hydroxide NaOH to produce aqueous sodium sulfate Na SO and liquid water H O If 9 19 g of sodium sulfate is produced from the reaction of 23 5 g of sulfuric acid and 32 3 g of sodium hydroxide calculate the percent yield of sodium sulfate Be sure your answer has the correct number of significant digits in it
Physical Chemistry
GeneralUse the References to access important valu general chemistry student found a chunk of metal in the basement of a friend s house To figure out what it was she used the ideas just developed n class about density She measured the mass of the metal to be 143 4 grams Then she dropped the metal into a measuring cup and found that it displaced 19 6 mL of water Calculate the density of the metal Density g mL Densities of Some Common Substances Substance Density g mL Water Aluminum 2 72 Chromium Nickel Copper Silver Lead Mercury Gold 1 00 Tungsten Platinum 7 25 8 91 8 94 10 50 11 34 13 60 19 28 19 38 21 46 A 55 83 F Previous Next 70 440 5 4
Physical Chemistry
GeneralAmmonium perchlorate NH CIO is a powerful solid rocket fuel used in the Space Shuttle boosters It decomposes into nitrogen N gas chlorine C1 gas oxygen 0 gas and water vapor releasing a great deal of energy Calculate the moles of ammonium perchlorate needed to produce 2 10 mol of oxygen Be sure your answer has a unit symbol if necessary and round it to the correct number of significant digits
Physical Chemistry
GeneralA student is conducting a lab in order to contribute to further research Data has been recorded and requires further analysis Element Isotope Name and Atomic Mass X Z X 24 mass of 23 985 X 25 mass of 24 986 X 26 mass of 25 983 Y 12 mass of 12 000 Y 13 mass of 13 0033 Abundance 78 99 10 00 11 01 98 93 1 07 19 9 Z 10 mass of 10 0129 Z 11 mass of 11 0093 80 1 5 Average atomic mass of sample 74 95 amu 12 01 amu 10 81amu Which statement gives the best explanation for whether or not all the information provided can or cannot be used for further research purposes The data cannot be used for further research because some of it is incorrect The average atomic mass is calculated incorrectly for elements Y and Z The data can be used for further research because it is correct The average atomic mass is recorded in detail for the represented isotopes The data can be used for further research because it is correct The data is a representation of the experiment being done on the represented isotopes The data cannot be used for further research because some of it is incorrect The average atomic mass is calculated incorrectly for element X
Physical Chemistry
GeneralWhich of the following could enter into H bonding interactions with water Choose all that apply CH CH OH SH U CH CH CH CH CH3 CH3 CH CHCH OCH None of the Above 4
Physical Chemistry
GeneralThe pictures below show two reactions that release large amount of energy N Reaction I N proton N neutron N N Reaction 2 N N Which sentence identifies the process that is happening and explains what is being produced Reaction 1 is fusion because 2 isotopes of hydrogen are combining to form a Helium with a heavier nucleus Reaction 2 is fusion because 2 isotopes of helium are combining to form a Hydrogen with a heavier nucleus Reaction 2 is fusion because 2 isotopes of hydrogen are combining to form a Helium with a heavier nucleus Reaction 1 is fusion because 2 isotopes of helium are combining to form a Hydrogen with a heavier nucleus
Physical Chemistry
GeneralAn unknown element Z is a dull brittle powder that reacts with oxygen at high temperatures Reaction of 0 665 gram of 2 with oxygen under two different sets of conditions forms gaseous products with masses of 1 328 g and 1 660 g What is the approximate atomic mass of the element O 12 32 24 48
Physical Chemistry
GeneralFor the following reaction 3 86 grams of nitrogen monoxide are mixed with excess hydrogen gas The reaction yields 1 67 grams of nitrogen gas 2NO g 2H g N g 2H 0 1 1 What is the theoretical yield of nitrogen gas 2 What is the percent vield for this reaction grams
Physical Chemistry
Generalor the following reaction 4 28 grams of aluminum are mixed with excess iron III oxide The reaction yields 6 59 grams of aluminum oxide Fe 03 s 2AI s Al2O3 s 2Fe s 1 What is the theoretical yield of aluminum oxide 2 What is the percent yield for this reaction grams
Physical Chemistry
GeneralConsider the endothermic reaction Cl g 2Cl g If the reaction mixture is at equilibrium which disturbances increase the amount of product the most O increasing the temperature and increasing the volume O decreasing the temperature and decreasing the volume decreasing the temperature and increasing the volume O increasing the temperature and decreasing the volume
Physical Chemistry
Generalentify the species oxidized the species reduced the oxidizing agent and the reducing agent in the following electron transfer reaction 2Al s 3Cl g 2A1 aq 6Cl aq species oxidized oxidizing agent species reduced reducing agent As the reaction proceeds electrons are transferred from to
Physical Chemistry
GeneralFor the following reaction 28 0 grams of nitrogen gas are allowed to react with 64 0 grams of oxygen gas N g O g 2NO g What is the FORMULA for the limiting reagent What is the maximum amount of nitrogen monoxide that can be formed What amount of the excess reagent remaing grams
Physical Chemistry
Generalfor this questio a How many grams of barium hydroxide Ba OH 2 are present in 2 63 moles of this compound grams b How many moles of barium hydroxide are present in 4 39 grams of this compound moles
Physical Chemistry
General12 Determine the net ionic equation for the following chemical reaction NH4OH aq HCl aq Hint HCl aq is strong acid and NH4OH aq is weak base H2 g Cl2 g 2HCl aq NH4OH aq H aq NH4 aq H2O l O NH4OH aq H aq NO g 3H2 g O H aq OH aq H2O l
Physical Chemistry
GeneralComplete the following tables Symbols are as they appear on the Periodic Table Atomic numbers are from 13 to 26 Name Symbol Name chlorine sulfur calcium
Physical Chemistry
GeneralSee if you can complete the following table using only what is on this page Hint Two of the entries are for the same eleme Element Symbol Nuclear Atomic Mass Symbol Number Number 14N Na 20 Protons Neutrons Electrons 7 8 11
Physical Chemistry
GeneralWrite a formula for the compound formed between each of the pairs of ions given in the table Cation Formula Zn K Ni Anion Formula Compound Formula CH3COO NO PO 3
Physical Chemistry
GeneralWhich of the following elements are nonmetals Z atomic number Choose all that apply Br Z 35 Ov Z 23 Cs Z 55 P Z 15
Physical Chemistry
GeneralClassify the underlined property as chemical or physical When aluminum foil is placed into liquid bromine a white solid forms Iodine is a purple solid that melts at 114 C The colorless gas hydrogen reacts explosively when ignited in air
Physical Chemistry
General2 Writing electron configurations a Elements 1SP 19K 26Fe 29Cu 35 Br 38Sr 42Mo 48Cd