Chemistry Questions and Answers July 29, 2020

Two isotopic compounds are produced in the synthesis of a new therapeutic drug, which must be separated by repeated chromatography cycles. In each cycle, the solution containing both compounds passes through a chromatography column of length L 65.0 cm containing N theoretical plates. The compounds have a separation factor (adjusted relative

When the Hg concentration is 4.16x104 M, the observed cell potential at 296K for an electrochemical cell with the following reaction is 1.930v. What is the Ma concentration Hg (aq) Mn(s) Ho(1) Mn(aq) Answer M

60. Place the following in order of decreasing metallic character As K P a) P As K b) As P K c) K P As d) As K P e) K As P 61. Which has the largest electronegativity B) Sn C) Sb D) Te E) I 62. The electronegativity for carbon and sulfur is 2.5. Therefore, the compound CS2 would be expected to A) Br a) be ionic with C as the anion. b) be

1) how could you separate gold from a mixture of zinc andgold? 2) complete and balance the following chemical reactions? Pb(NO3)2(aq)+2KCL(aq)-> Ba(NO3)2(aq)+Na2SO4(aq)-> K2CO3(aq)+Ba(NO3)2(aq)-> HCl(aq)+AgNO3(aq)-> 3) Using a hydrochloric acid solution, how could you determinewhether a white powder was zinc sulfide or silver nitrate?

Answer the following questions for 1,3,5-hexatriene, the conjugated triene containing six carbons. 1) Which p molecular orbitals belong in the following categories? Select all that apply A) Bonding: p 6*, p 5*, p 4*, p 3 , p 2, p1 B)Antibonding:p 6*, p 5*, p 4*, p 3 , p 2, p1 2) Select which p molecular orbital is the: A) Homo: p 6*, p 5*, p 4*, p

An average reaction rate is calculated as thechange in the concentration of reactants or products over a periodof time in the course of the reaction. An instantaneousreaction rate is the rate at a particular moment in thereaction and is usually determined graphically. The reaction of compound A formingcompound B was studied and the following data

5) When KCl dissolves in water A) the Cl ions are attracted to dissolved K ions. B) the CI ions are attracted to the partially negative oxygen atoms of the water molecule. C) the K ions are attracted to Cl ions on the KCl crystal. D) the K ions are attracted to the partially negative oxygen atoms of the water molecule. E) the K ions are attracted

2382U4Heon In the above reaction the atomic number is the symbol is and the atomic mass is

The air in a bicycle tire is bubbled through water and collectedat 25 ?C. If the total volume of gas collected is 5.30 L at a temperatureof 25 ?C and a pressure of 738 torr , how many moles of gas was inthe bicycle tire?

Based on the periodic table, sort the resulting ions according to size related to the parent atom.

10 Question (1 point) Based on the periodic table, sort the resulting ions according to size related to parent atom. See page 3

Arrange the acids shown from lowest pk, to highest pKa by clicking and dragging them into position. O lowest pka OH HN OH highest pka

Which answer best describes the transfer of heat that occurswhen 1.20 mol of H2 reacts? given 2H2 + O2 -----> 2H2O delta H rxn = -484 kJ the answer includes kJ released or absorbed

A battery is constructed based on the oxidation of magnesium andthe reduction of Cu2+. The initial concentrationsof Mg2+ and Cu2+ are1.210 ?4 M and 1.5 M , respectively,in 1.0-liter half-cells. A)What is the initial voltage of the battery? B)What is the voltage of the battery after delivering5.0 A for 8.0 h ? C) What are the concentrations of Mg

The absorption spectrum of the complex ion[Rh(NH 3 ) 6 ] 3+ has a maximumabsorbance at 295 nm. Calculate the crystal field splitting energy(in KJ/mol) for this ion.

Amphetamine (C9H13N) is a weak base with a pKb of 4.2. Calculate the pH of a solution containing an amphetamine concentration of 219 mg/L.

Arrange the fertilizers in decreasing order of mass percentage of nitrogen. Highest percent nitrogen (NH,)H,PO. (NH4)SO4 (NH,),HPO, NH NO, KNO, NH3 Lowest percent nitrogen Answer Bank 4 O

7. An endothermic reaction causes the surroundings to A. release CO B. condense C. warm up D. decrease in temperature E. become acidic

Acetanilide is not the fastest of the three compounds to react with Br. Shown below are 4 resonance structures for the anti acetanilide paraarenium bromination ion. Give the number of the one that should be the least contributing and briefly explain why. H I CH3 CH3 some Diyar Br H Br H Br 3 NH CH3 Br Br Br The substituents in all three compounds

5. Which of the following reactions is a redox reaction? (a) K2CrO4 + BaCl2 ? BaCrO4 + 2KCl (b) Pb22+ + 2Br- ? 2PbBr (c) Cu + S ? CuS The answer sheet says just C, but shouldn't it be B and C since Lead seems to be gaining an electron in order to bond with Br (ie it is going from 2+ to just 1+)? Please explain why I am incorrect if I am.

5. Which of the following reactions is a redox reaction (a) KCrO4 BaCl BaCrO4 2KC1 (b) Pb 2Br 2PbBr (c) Cu S CuS. A a only B b only C c only D a and c E b and c

What is the boiling point of water at an elevation of 1.15104ft ? Enter your answer numerically, in degrees Celsius.

show all work please!

w 4. Label the following compounds as having R or S configuration around the stereocenter(s). HO H OH 1l 21 HP 20 rksheet 3 Stereochemistry HOPHO Br 1 R 300 1 201 CI H H F 2 H H Cl.....C 3 1S 2R HS SH 1 3 carbon Inoncalo 2

acid-base titration lab! any help i can get would be amazing:)

V25ml HCl C 0.1 M Acid Base Titration LAB V C2 1st pink 11 mL in burette, somLin 2nd pink 10.SmL in burette, somLin BuretteNaOH100mL PipetteAc50mL Phenolphthalein indicatur coloruss in acid, pink in base transition point Nevtralization point

(a) Analyze the following pair of compounds. Which of the terms explains the relationship between the two compounds? Select all that apply. (b) Disaccharides are joined by glycosidic bonds formed between the anomeric carbon on one monosaccharide and a hydroxyl (?OH) group of another monosaccharide. Identify the types of linkages in each of the

OH CHOH OH OH OH aDgalactose OH CHOH OH OH OH BDgalactose enantiomers anomers epimers diastereomers

Answer the questions below concerning the following graph. What type of spectrum is shown UVVis NMR IR What type of electromagnetic radiation is associated with the peak (at 278 nm) Radio waves Infrared radiation Ultraviolet radiation. Visible light Absorbance 0.06 0.05 0.04 0.03 0.02 0.01 Tryptophan 250 What is measured in this spectroscopic

1) For the substituted cyclohexane compound given below, highlight the groups - by clicking on atoms - that will sterically interact with the methyl group in a 1,3-diaxial fashion. 2) For the substituted cyclohexane compound given below, highlight the groups - by clicking on atoms - that will sterically interact with the methyl group in a

CI CH3 I. I Br H H

(7 pts) WRITTEN ENTER ANSWER ON WRITTEN TEMPLATE Consider the molecule PSBr. P is the central atom in the molecule, and the 5 and Br atoms are all terminal atoms. Draw the correct Lewis structure for this molecule. Be sure to draw all lone pairs, and label all nonzero formal charges on each atom. If multiple resonance structures are possible, draw

PART A: Balance each redox reaction occurring in acidic aqueous solution. MnO4( a q )+Al( s )Mn2+( a q )+Al3+( a q ). Express your answer as a chemical equation. Identify all of the phases in your answer. PART B: The half-cell is a chamber in the voltaic cell where one half-cell is the site of the oxidation reaction and the other half-cell is the

Assign oxidation states to all the elements in this unbalancedreaction: Ag + (aq) + Cu(s) --> Ag(s) + Cu 2+ (aq) Which substance gets oxidized? Which substance gets reduced? Balance the Redox reaction.

Analyze each of the following cycloaddition reactions and answer the accompanying questions. Which statements are true This reaction is thermally allowed. The thermal transition state is aromatic. This reaction is photochemically allowed. This reaction is photochemically forbidden. The thermal transition state is antiaromatic. This reaction is

During your design of a product, Taguchi loss equation is used to understand financial loss due to deviation from your target specification. Your target specification is 25 mm where deviation range is + or - 1mm. At boundary values of deviations, it costs you about $100 for each repair. Find out the value of k and estimate the value of financial

The volume of oxygen at N.T.P obtained from decomposition of 1 liter 100 volume of H 2 O 2 is a)100 liter b) 10 liter c)1 liter d)200 liter

Which of the following solution has osmotic pressure nearest to that of an equimolar solution of K 4 [Fe(CN) 6 ] a) C 12 H 22 O 11 b) Al 2 (SO 4 ) 3 c) Na 2 SO 4 d)BaCl 2

What would be least acidic for both ?

5. Which is the most acidic hydrogen in the compound shown II 4 20000 III IV V Ans A Topic Relative Acidities Section 18.1 Difficulty Level Medium IV 6. Which is the most acidic hydrogen in the compound shown II H E) V Ans B H B) II C) III D) IV IV H III H H III

If the atmospheric pressure is 0.980 atm , what is thepressure of the enclosed gas in each of the three cases depicted inthe drawing (Figure 1) ? Part A What is the pressure of the enclosed gas in (i)? Assume that thegray liquid is mercury. Express your answer using two decimal places. Part B What is the pressure of the enclosed gas in (ii)?

Figure 1 of 1 Open end Gas h h 52 cm (i) Open end Gas h h 67 cm (ii) Closed end Gas h 10.3 cm (iii)

macmillan learning For the amino acids given, highlight the specified atom or group of atoms by clicking on them. (b) Select the ycarbon in glutamate. (a) Select the acarbon atom in threonine. HN HCOH H (c) Select all the atoms in the side chain in alanine. HN H H H HN H HCH HCH FORMA LE

For each bond, show the direction of polarity by selecting the correct partial charges. CN C0 ON The most polar bond is 12 For each bond, show the direction of polarity by selecting the correct partial charges. TeSe OTe OSe Y CIS ClSi Y The most polar bond is For each bond, show the direction of polarity by selecting the correct partial charges.

When exposed to sodium hydroxide, Aspartame can undergo saponification. Draw the expected product of the reaction. Then, using pKa values for the 1 fully protonated forms of aspartic acid (pkas 1.9, 3.7, and 9.6) and phenyl alanine (pkas 1.8 and 9.1), estimate what the pH at which the new product formed will be neutral. pka (OH) 2.9 HO By HN pKa

How developing countries can nurture their domestic industries through establishing a robust industrial policy, which often works to the detriment of existing companies. What are those policies? Also, the book describes various countermeasures, such as Cautious activism, Reciprocity and Aggressive Unilateralism etc. What are the strengths and

8. We dissolve 2.45 g of sugar in 200.0 g water. What is the mass percent of sugar in the solution (A) 1.21 B) 1.23 C) 2.42 D) 123 E) none of the above 9. What is the mass percent of a solution prepared by dissolving 18.9 grams of solid into 39.5 grams of water A) 47.8 B) 58.4 (C) 32.4 D) The identity of the compound must be known. E) none of the

Part B Based on the given data, how many extra electrons did drop C contain Express your answer as an integer. Submit electrons Hints My Answers Give Up Review Part, Millikans OilDrop Experiment Learning Goal To analyze the experiment used to determine the properties of an electron. In 1909, Robert Millikan performed an experiment involving tiny,

How much copper can be obtained from 100 g of copper sulphate (CuSO4)

Q. What was old concept of an atom

Q. What are the Daltons assumptions about the model of an atom And explain.

Q. Define the word fundamental particles. Fundamental particles.

Atomic number Q.Explain the term atomic number.

Mass number Q.Define mass number.

Isotopes and isobars Q.Define isotopes

Q. Give the list of isotopes of elements

Characteristics of isotopes. Q. Write the characteristics of isotopes.

Define Isobars

Q. Explain the discovery of radioactivity.

Atomic Spectra Q.Explain atomic Spectra

Nature of light Q. Why corpuscular theory was rejected

Salien. features of the wave theory. Q. Write the salient features of wave theory of light.

Wave motion and its characteristics Q. Explain wave motion of light and its characteristics

Q. Describe the Plancks quantum theory of radiation

Q. Describe photoelectric effect.

Arrange the following in order of increasing bond strength ofthe carbon oxygen bond: Carbon monoxide < carbonate ion < carbon dioxide carbonate ion < carbon dioxide < carbon monoxide Carbon dioxide < carbon monoxide < carbonate ion Carbon monoxide < carbon dioxide < carbonate ion Carbon dioxide < carbonate ion <

CONCEPTUAL NECTION 17.5 Buffer Capacity A 1.0L buffer solution is 0.10 M in HF and 0.050 M in NaF. Which action destroys the buffer (a) adding 0.050 mol of HCI (b) adding 0.050 mol of NaOH (c) adding 0.050 mol of NaF (d) none of the above

A buffer contains significant amounts of acetic acid and sodiumacetate. Write an equation showing how this buffer neutralizes added acid(HNO3). Express your answer as a chemical equation. Write an equation showing how this buffer neutralizes added base(Ca(OH)2). Express your answer as a chemical equation.

B. How does this compare to the solubility of Mg(OH)2 in pure water? (S1S/S1S=?)

Calculate the solubility (in grams per 1.00 x 10 mL of solution) of magnesium hydroxide in a solution buffered at pH 12. Express your answer using two significant figures. IVE x Xb x x x IXI X.10n S You have already submitted this answer. Enter a new answer. No credit lost. Try again. g(1.00 10 mL)

13. Draw the best Lewis structure for the free radical, NO2. What is the formal charge on the N 14. Place the following in order of increasing bond length. CF CBr CCI 15. Draw the best Lewis structure for CH3. What is the formal charge on the C,16. Which of the following are allowed resonance forms of NCS I NCS A) only I II NC3 and ENCS 3 and

Balance each of the following redox reactions occurring inacidic aqueous solution. Part A Zn(s)+Sn2+(aq)?Zn2+(aq)+Sn(s) Express your answer as a chemicalequation. Identify all of the phases in your answer. Part B Mg(s)+Cr3+(aq)?Mg2+(aq)+Cr(s) Express your answer as a chemicalequation. Identify all of the phases in your answer. Part C

Add electron dots and charges as necessary to show the reaction of calcium and oxygen to form an ionic compound. int Ca Neutral atoms 0 Ca lons Previous Up View Saletion O Check Answer Next E,Rank these elements according to electronegativity. Most electronegative Least electronegative Al Cs F C Na

Build a two-dimensional crystal that contains six formula units of sodium chloride in the solid state

What are the advantages of using a solvent pair for recrystallization Select all that apply. You can quickly make the solution supersaturated by adding more of the solvent with greater dissolving power. You can calculate the precise amounts of the solvents needed for recrystallization. You can quickly make the solution supersaturated by adding

For each bond drawn below, indicate the direction of bond polarity. Click in the blue box to toggle the arrows direction leave the box blank for a completely nonpolar bond. F CH3 H3C NH Br Mg CH3,Two reactions between a Grignard reagent and a carbonyl compound are given below. Draw the main organic product for each reaction and indicate if H or H

21.0mL of 0.117M sulfurous acid (H2SO3) wastitrated with 0.1019M KOH a-at what added volume of base does the first equivalence pointoccur? b-at what added volume of base does the second equivalence pointoccur?

9) How many molecules of nitrogen monoxide are in a 22.5 gram sample A) 5.86 x 103 B) 7.33 x 1023 C) 4.51 x 1023 D) 4.06 x 1023 N Os 2259 ( 10) When water is heated, bubbles form in the water. Is this evidence of a chemical reaction Why A) No, boiling water is a physical change. BYes, the formation of a gas is evidence of a chemical reaction. C)

For each of the 3 ionic compounds, select the main group element"X" belongs to... a) X3PO4 b) CaX2 c)X2(SO4)3

Arrange the ionic compounds in order of increasing latticeenergy: LiF, NaF, MgO, CaO

Question 9 Arrange the ionic compounds in order of increasing lattice energy LiF, NaF, MgO, CaO LiF NaF MgO CaO NaF LiF MgO CaO CaO MgO NaF LiF MgO CaO LiF NaF CaO MgO LiF NaF NaF LiF CaO MgO MgO CaO

What is the anode in an alkaline battery?? ------ Describe the electrodes in this nickel-copper galvanic cell. a. Drag the appropriate items to their respective bins. anode cathode gains mass loses mass Nickel Copper b. The standard reduction potential for a substance indicateshow readily that substance gains electrons relative to othersubstances

Balance each of thefollowing half-reactions, assuming that they occur in basicsolution. You may want toreference (Pages 757 - 761) Section 18.1 while completing thisproblem. Part A O2(g)?OH?(aq) Express your answer as a chemical equation includingphases. Part B H2O(l)?H2(g) Express your answer as a chemical equation including phases. Part C

Please show how you get the answer

on 2 well, sketch the following (e) 111 (g) 123 (n) 122 (h) 103 or the directions shown cell 3.57 Determine indices for the directions shown in the following hexagonal unit cells a3 a3 (a) 1 T ay 2 a1 a3 a3 (b) 1 a ay a1 (c) (d) 3.58 Sketch the 1123 and 1010 directions in a hexagonal unit cell.

835.6 MHz (common frequency used for cell phone communication)Calculate the wavelength of each of the following frequencies ofelectromagnetic radiation.

A) What is the approximate value of the normal meltingpoint? B) Below what pressure value will solid neon sublime? C) At temperature T = - 240 ?C can neonbe liquefied by compressing it?

Use the phase diagram for neon to answer the following questions Pressure (atm) 10 10 10 1 101 102 103 Solid 20 Liquid Triple point 40 Supercritical fluid Critical point 60 Temperature (K) Gas 80 100 You may want to reference (Pages 457459) Section 11.6 while completing this problem.

A. What is the pH at the equivalence point? B. What is the volume of added acid at the equivalence point? C. At what volume of added acid is the pH calculated by working an equilibrium problem based on the initial concentration and Kb of the weak base? D. At what volume of added acid does pH=14-pKb? E. At what volume of added acid is the pH

hile completing this problem. jure Hd 14 12 10 8 6 4 2 20 0 0 10 20 30 40 50 Volume of acid added (mL) Type here to search 1 of 1

The bond angle marked a in the following molecule is about HIN A. 90 B. 109.5 C. 120 HNC C0H D. 60 H E. 180 .. O O H a

8) Which of the following compounds exhibits hydrogen bondingim A) CH31 autes 3001 seUrs ma B) HBr C) CH3OCH3 D) CH3NH2 good 19) What is the strongest type of intermolecular force present in Cl2 A) iondipole B) dipoledipole C) dispersion D) hydrogen bonding E) none of the above on ni siduloe tzom od lliw zbauos (HOCHOCHOCH HOCHOCHO 20) What type

44) KBr does not dissolve well in nonpolar solvents because A) solutesolute interactions are much larger than solventsolvent or solutesolvent interactions. B) solventsolvent interactions are much larger than solutesolvent or solutesolute interactions. C) solutesolvent interactions are much larger than solventsolvent or solutesolute interactions.

Calculate ? H rxn for the followingreaction: 5C( s )+6H2( g )?C5H12( l ) Use the following reactions andgiven ? H ?s. C5H12( l )+8O2( g )?5CO2( g )+6H2O( g ), ? H = -3244.8 kJ C( s )+O2( g )?CO2( g ), ? H = -393.5 kJ 2H2( g )+O2( g )?2H2O( g ), ? H = -483.5 kJ Express your answer to for significant figures.

arch Be sure to answer all parts. Choose all possible values of each quantum number for the outermost electron in an Rb atom. 01 0 23 4 5 6 7 8 m my 3 attempts left Check my work 2 3 0 4 54 10 5 1120 12 1 Prev 3 of 56 www Next Fi

Avogadros number is 6.02x1023 atoms per mol. How many atoms of O do I have in 64.0 g of 02 1.80x1024 O 1.20x1024 O2.40x1024 6.02x1023 of O atoms of O atoms of O atoms of O atoms

Assuming ideal behavior, what is the density of argon gas atSTP, in g/L?

Add formal charges as necessary to the following structure. All unshared valence electrons are shown. -- Please show the charges on the picture. In addition, what is the net charge on species?

Add formal charges as necessary to the following structure. All unshared valence electrons are shown. 0 0C8 0 What is the net charge on the species

According to Boyles Law, the pressure of a gas increases as the volume decreases because the gas particles strike the walls of the container with more force. the kinetic energy of the gas particles increases. the temperature of the gas increases. the gas particles strike the walls of the container more often. the gas particles get bigger. 0 0 0 0 0

Arrange these oxoacids (oxyacids) according to acid strength. HIO HBrO HCIO Most acidic Least acidic Answer Bank

Balance the following reaction, which occurs in acidic solution. Cr 2 O 7 2- (aq) + I - (aq)--> Cr 3+ (aq) + IO 3 - (aq) Please show the steps involved to balance the reaction. Thanks in advance!

Calculate the concentration of all species in a 0.180 M solution of HCO3. Enter your answers numerically separated by commas. Express your answer using two significant figures. HCO3, HCO, CO, H3O, OH 5 1990 M

An attempt at synthesizing a certain optically active compound resulted in a mixture of its enantiomers. The mixture had an observed specific rotation of +12.1 degree. If it is known that the specific rotation of the R. enantiomer is -32.4 degree, determine the percentage of each isomer in the mixture R enantiomer:_________% S enantiomer:_________%

Analyse the IR of bromobenzene. Use letters (a, b, c, ...) underidentity, then label the peaks with the specific letters + theidentity on the chart. Thank YOU IR wavenumber identity**

LOD TRANSHITTANCE1 D Bromobenzene 4000 3000 2000 HAVENUMBERII 1500 TT 1000 500

Ammonia can also be synthesized by this reaction: 3H2(g) + N2(g) ? 2NH3(g) What maximum amount of ammonia in grams can be synthesized from25.2 g of N2 and8.42 g of H2? What maximum amount of ammonia in kilograms can be synthesizedfrom 5.22 kg of H2 and31.5 kg of N2? Express your answer in kilograms to one decimal place. For the reaction shown,

Assign formal charges to each atom in the O3 molecule shownhere. Be sure to click the or button before clickingon the molecule.

De Broglies Equation Q. Explain De Broglies Equation

Hinsberg uncertainty principle. Q. Describe Heisenberg uncertainty principle

Concept of atomic orbitals Q. Describe Scrodinger wave theory

Explain Concept of orbital?

Quantum numbers Q. What are quantum numbers

Shapes of orbitals Q. Describe the shapes of s, p and dorbitals Sorbital

Define EC and valence shell EC

State and explain Aufbau principle Aufbau principle