General Questions and Answers

4Al 2 2 3 1 How many grams of O are needed to make 45 moles of Al O3 1 Show Work 1 Final Answer

Do the following have Covalent lonic or Metallic Bonds TiO Ni SO Na PO

Elemental Potassium is added to a solution of Calcium Nitrate Write out the left side of the reaction list what type of reaction will occur predict the products predict all states of matter and balance the equation

17 Complete the table for the following molecules Water H O Methane CH H Total of valence e 3D Lewis structure Bond angle Polarity H H water methane ammonia carbon dioxide Ammonia NH Carbon dioxide CO LOS

Name Kinetics Dry Lab CHM 1046 Reminder include proper significant figures and units as appropriate for your answers 1 For the reactions given below what is the instantaneous rate for each of the reactants and products In other words express the rates of the products and the reactants in terms of changes in concentration with time for the following reaction a 4 H3PO3 3 H3PO4 PH3 b 2 As2S3 9 02 2 As2O3 6 SO2 c 2 Sb 3 Cl2 2 SbCl3

4A 2 1 How many grams of O are needed to make 45 moles of Al O3 2 3 1 Show Work 1 Final Answer 2 How many grams of Al O3 are produced from the reaction of 26g of O 1 Show Work 1 Final Answer

What quantity of energy does it take to convert 0 100 kg ice at 20 C to steam at 250 C Specific heat capacities ice 2 03 J g C liquid 4 2 J g C steam 2 0 J g C 40 7 kJ mol AHfus 6 02 kJ mol AH vap Energy kJ

What is the percent composition of Na3PO4 Show your work

If you have 50 mol of Ca OH 2 how many grams would it weigh

Scoring Your score will be based on the number of atcries minus the number o Which solvent water or hexane C6H 4 would you choose to dissolve each of the following Water Hexane CS HF C6H6 CH OH Clear All CH3 CH2 15 CH OH

Aztec Civilization A D 1200 to 1535 Her Jame Inca Civilization A D 1200 to 1535 Source Sue A Kime World Studies Global Issues and Assessments N N Publishing 1995 adapted from NYS Global History and Geography Regents Exam August 2005 1 23 Por each record on your separate answer sheet the number of the word or expression that of those given best completes the statement or answers the question Review later 18 These illustrations suggest that early Latin American civilizations 1 were based on European societies 2 used advanced technology to build complex structures 3 incorporated early Roman architectural design 4 were strongly influenced by Renaissance humanism Review later 19 Which of the following geographic challenges did the Aztec civilization face 1 Building structures that could survive hurricanes 2 Controlling a river that regularly flooded 3 A lack of farmland near their capital city

Pentane C5H12 and hexane C6H14 form an ideal solution At 25 C the vapor pressures of pentane and hexane are 511 and 150 torr respectively A solution is prepared by mixing 25 mL pentane density 0 63 g mL with 30 mL hexane density 0 66 g mL a What is the vapor pressure of the resulting solution Protal torr b What is the composition by mole fraction of pentane in the vapor that is in equilibrium with this solution Xpen An error has been detected in your answer Check for typos miscalculations etc before submitting your answer

24 In a laboratory the student determines the mass of magnesium chloride to be 36 00 g A Calculate the gram formula mass of magnesium chloride s B What is the percent composition of chlorine in the product C Calculate the number of moles of magnesium chloride s produced D Calculate the number of ions produced

What quantity of energy does it take to convert 0 500 kg ice at 20 C to steam at 250 C Specific heat capacities ice 2 03 J g C liquid 4 2 J g C steam 2 0 J g C AHvap 40 7 kJ mol AHfus 6 02 kJ mol Energy kJ

shorter 4p 2s increases 3p 2s longer decreases According to the quantum mechanical model as the quantum number n increases the energy and the spacing between the energy levels Therefore the transion transition would have a greater energy difference than the Lower energy is associated with transition would produce a longer wavelength wavelengths thus the

What is the vapor pressure of a nonvolatile solution made by adding 166 g glycerin C3H803 to 333 mL H 0 at 39 8 C The vapor pressure of pure water at 39 8 C is 54 torr and its density is 0 992 g mL HOW DO WE GET THERE What is the amount of water in moles mol H O

What is the composition of a methanol CH3OH propanol CH3 CH CH OH solution that has a vapor pressure of 86 2 torr at 40 C At 40 C the vapor pressures of pure methanol and pure propanol are 303 and 44 6 torr respectively Assume the solution is ideal Mole fraction of methanol Mole fraction of propanol

26 Define acid and base according to the Arrh cont media to noites

If 213 g of water is added to 88 g of a 1 8 m NaCl solution what is the mass percent of NaCl in the diluted solution Mass percent

12 The percent composition of an unknown substance is 75 42 Carbon 6 63 Hydrogen 8 38 Nitrogen polor mass is 334 00 mol what is its empirical and molecular formula 8pts

13 There are 10 0 g of sucrose and 10 0 g of oxygen reacting a How much water can form b which is the limiting reagent c How much excess is there d If the actual yield is 4 56g of water what is the percent yield 10pts 13 CH2011 120 12C0 11H 0

Questions Circle the questions that have been assigned 1 Identify a chemical reagent used in this experiment that can be used to distinguish solid CaCl soluble from solid CaCO insoluble What is the distinguishing observation 2 What test reagent used in this experiment will distinguish a soluble CI salt from a soluble SO salt What is the distinguishing observation 3 Predict what would be observed and why from an aqueous mixture for each of the following all substances are water soluble a potassium carbonate and hydrochloric acid b zinc chloride and silver nitrate c magnesium chloride and sodium hydroxide d ammonium nitrate and sodium hydroxide 4 Three colorless solutions in test tubes with no labels are in a test tube rack on the laboratory bench Lying beside the tests tubes are three labels 0 10 M Na CO3 0 10 M HCl and 0 10 M KOH You are to place the labels on the test tubes using only the three solutions present Here are your tests A few drops of the solution from test tube I added to a similar volume of the solution in test tube 2 produces no vis ible reaction but the solution becomes warm se only do A few drops of the solution from test tube 1 added to a similar volume of the solution in test tube 3 produces carbon dioxide gas thwest o ajone Identify the labels for test tubes 1 2 and 3

RCH CHR ill either RCO3H cis trans 1 Cl H O 2 CH3O Na RHC CHR oxirane A The two reactions above show routes for conversion of an alkene into an oxirane If the starting alkene is cis 2 butene the configurations of the oxirane products A and B are roduct A roduct B RHC CHR oxirane B two oxirane products rotate the plane of polarization of plane polarized light

Holds sperm EP I It s located on the back of each testicle Your epididymus can be felt from outside the scrotum very tiny tissue Sperm doesn t sit in there forever If it s not used willingly ie sex masturbation then it will leave the body unwillingly wet dream The testicles make more sperm Wet Dreams are completely functioning body No big deal A sign of a healthy

What is the objective purpose of this experiment In other words describe what were you trying to accomplish by doing this experiment Methods Procedure 1 What is the source complete reference from which you acquired the procedure 2 If your own procedure differs from the procedure referenced above please explain in detail how it differs Results Summarize data obtained in tabular form A Pre Lab Table 1 Effect on mp of mixing two compounds Urea 100 80 60 40 20 0

a Determine the volume a gas will occupy at 95 C and 325 kPa if it occupies 0 925 L at 32 C and 95kPa b If the temperature had remained constant at 32 C i What law can be used ii What would have been the volume

What is the element Ar classified as in the periodic table O a noble gas O a halogen O a metalloid O a metal

Metallic rubidium crystallizes in a body centered cubic lattice with one Rb atom for each point in the crystal lattice How many atoms are there per unit cell If the edge length of the unit cell is found to be 559 pm what is the metallic radius of Rb in pm

3 The extinction coefficient for a particular chemical is 20 0 cm mol L The absorbance for a sample of a solution made from this chemical is found to be 0 850 Using Beer s Law calculate the concentration M of the solution Path length b 1 00 cm

ammonia reacts with oxygen to form nitric oxide and water vapor INH3 5024NO 6H2O What is the theoretical yield of water in moles when 40 0 g NH3 and 50 0 g 02 are mixed and allowed to react A 1 87 mol B 1 30 mol C None of these D 1 57 mol E 3 53 mol

4 19 2 00 q MCA T water 1 19 ice 2 009 1 6x102 4 How much energy is required to transform 5 0g of ice into water at 0 0 C water Sog ice 60 110 200 I 4 1 KI 1000g 1 7 kJ 5 Using the answers from question 3 and 4 how much energy is required to take 5 0g of ice at 15 C to water at 0 0 C 1 8 kJ 6 How much energy is released from 50 g of water going from 50 C to ice at 10 C Q mcat Sog 419 g c 600 OLJOB TE JASH 50 1100 anioifegu 6 nd narud g 08 A I gried ybod

What is the greenhouse effect a With a diagram explain what the greenhouse effect is i You must use the terms such as longwave radiation shortwave radiation greenhouse gases reflection energy in the explanation

Mass of Materials Complete the following table Mass of Penny Image of Measurement Include a piece of paper with your name and date g Calculation to mg mg Calculation to kg kg 2 49g Volume of Tap Water Complete the following table 2 mL Item 5 mL

2 Experimental Procedure Part A 2 Describe the technique for testing the odor of a chemical

4 What volume of 10 0 M NaOH must be used to prepare 650 0 mL of 0 800 M NaOH Show all your calculations Give your answer using correct number of significant figures

ess solutions in test tubes with no labels are in a test tube rack on the laboratory bench Lying beside the test tubes are three labels potassium iodide KI silver nitrate AgNO3 and sodium sulfide Na S You are to place the labels on the test tubes using only the three solutions present Here are your tests A portion of test tube 1 added to a portion of test tube 3 produces a yellow silver iodide precipitate A portion of test tube 1 added to a portion of test tube 2 produces a black silver sulfide precipitate a Your conclusions are Test tube 1 Test tube 2 Test tube 3 b Write the balanced equation for the formation of silver iodide Agl from a mix of two selected solutions provided above

4 A major textile dye manufacturer developed a new yellow dye The dye has a percent composition of 75 95 C 17 72 N and 6 33 H by mass with a molar mass of about 240 g mol Determine the molecular formula of the dye

5 The table shown below is taken from the experiment handout Read the handout and complete the missing final concentrations of bottle numbers 2 5 Use equation M V M V Note Show your work for at least bottle 2 and 3 Bottle Number 1 2 3 4 5 6 100 0 M dye mL 0 00 3 00 6 00 9 00 12 00 15 00 Distilled H O mL Final Concentration x 10 6 M 15 00 12 00 9 00 6 00 3 00 0 00 0 00 100 00

Lying beside the test tubes are three labels potassium iodide KI silver nitrate AgNO3 and sodium sulfide Na S You are to place the labels on the test tubes using only the three solutions present Here are your tests A portion of test tube 1 added to a portion of test tube 3 produces a yellow silver iodide precipitate A portion of test tube 1 added to a portion of test tube 2 produces a black silver sulfide precipitate a Your conclusions are Test tube 1 Test tube 2 Test tube 3

We can directly measure the temperature of a cup of coffee but we cannot directly measure its enthalpy Which statement explains why enthalpy cannot be measured directly Choose the correct answer Enthalpy is a measure of heat that is lost and this heat cannot be measured during a reaction while particles are moving Temperature has an absolute zero but enthalpy is a measure of energy transferred as heat and because particles always have energy enthalpy cannot be zero so we can only measure the change in enthalpy Temperature is measured by its effect on an external object with a thermometer while enthalpy never O affects substances outside the system so there is no way to directly measure the energy with a tool such as a thermometer Temperature measures the total kinetic energy of the particles in the coffee but enthalpy measures the average kinetic energy which cannot be found directly and must be calculated

11 58 Draw the cis and trans isomers for each of the following a 2 butene b 2 hexene

C Pectus scotatum Question 20 Pectus excavatum What does tactile fremitus assess B A Difference in density of lung tissue C Firmness of skin tissue Breath sounds

5 Experimental Procedure Part A The substances NaCl Na CO3 MgSO4 and NH4Cl which are used for test solutions are all soluble ionic compounds For each substance indicate the ions present in its respective test solution NaCl Na CO3

Magnesium Mg combusts in air to give a brilliant white light that has been used in photographic flashes and emergency flares How much heat is produced if 10 0 g Mg is combusted with excess oxygen gas Mg s O g MgO s AH 601 6 kJ mol Report your answer with three significant figures

Select the correct conversion factor for each step in the following roadmap for a substance with a density of 1 g mL 1g 1 mL 1000 kg 1g 1 kg 1000 g 1 mL 1g 1 mL 1000 L 1000 g 1 kg 1L 1000 mL 1000 mL 1 L 1g 1000 kg 1000 L 1 mL mass kg mass g volume mL

NE No Na Select one O Acid O Base CO Neutral FO Na O Na Identify this solution as an acid a base or a neutral solution

Answer these questions about dissociation reactions and precipitation reactions using letters a d below Which type s have a solid as the reactant Which type s have two reactants and two products Which type s involve ions Which type s have ions as reactants Choose Choose Choose Choose 44 41 4

Here is a complete ionic equation Ca 2 NO3 aq 2 Na aq S g Cas s 2 Na aq 2NO3 0 Ca and NOS Which two of the following are spectator ions in this equation Na 5

molecular equation H SO4 Ba OH 2 BaSO4 H2O Question 21 You have plenty of salts that are in front of you and you are trying to figure out which salts are soluble in water and which ones of their products are soluble in water For the following equation identify which reactants and products are soluble insoluble in water H SO4 Ba OH Use the editor to format your answer 1 Point Question 22 1 Point

Two chemical reactions are shown A 2Mg O2 2MgO B CaCO3 CaO CO2 Which statement is true O Both are synthesis reactions O Both are decomposition reactions A is a synthesis reaction and B is a decomposition reaction O A is a decomposition reaction and B is a synthesis reaction