Chemistry question and answers for September 02, 2023
- Q Determine the concentrations of the ionic species present in a0.285 M solution of the HO2CCH2CO2H . (pKa1 = 2.83 , pKa2 = 5.69).a) [ HO2CCH2CO2H ]b) [ HO2CCH2CO2- ]c)[ -O2CCH2CO2-...
- Q Calculate the concentration of all species in a 0.160M solutionof H2CO3.Enter your answers numerically separated by commas. Express youranswer using two significant figures.[H2CO3], [HCO?3], [CO2?3], [H3O+], [OH?]
- Q Explain why surface tension and viscosity decrease withincreasing temperature.Why do substances with high surface tensions also tend to havehigh viscosities?
- Q You make two dilutions. You take 82.19 mL of the stock solution(8.1×10-5M) and dilute to 500.0 mL tomake Solution #1. You then add 66.26 mL of Solution #1 to 30.11...
- Q Having trouble calculating the error of a diluted solution in a100mL volumetric flask. Concentration is 0.005 +/- 0.005M Amount ofConcentrated solution: 5.0mL +/- 0.1mL Volumetric flask: 100mL +/-0.08mLMy calculation so...
- Q For each of the following reactions, calculate ΔH∘rxn, ΔS∘rxn,ΔG∘rxn at 25 ∘C. State whether or not the reaction is spontaneous.If the reaction is not spontaneous, would a change in temperaturemake...
- Q 6. when choosing a solvent for recrystallization of an organicsolid, what rule of thumb is generally used? What characrsiticsshould an ideal recrystallizing solvent have?7. During recrystallization, why is it important...
- Q The mole fraction of glucose in an aqueous solution is 0.015.The density of the solution is 1.05 g/mL. Calculate the molarityand molality of the solution.
- Q Using an ice bath, cool 10mL of saturated sodium bisulfitesolution; then add, drop by drop, 5mL of 2-pentanone. Stir thesolution until there is precipitation of a solid. Add 25 mL...
- Q a gas has a volume of 3.80 L. at 0 C. what finaltemperature, in degrees Celsius, is needed to change the vine ofthe gas to each of the following, if...
- Q Suppose that you can reproduce a short-time physical or chemicalevent over and over again. Discuss possible sources of errorsassociated with measuring the duration of the event using astopwatch. (\"Human Error\"...
- Q 1. Calculate the pH of:A) 0.10 M ammonia (kb = 1.7 x 10 -5) .B) 0.15 M ammonium iodide (ka = 1.8 x 10 -5) .C) pure waterD) 0.15 M...
- Q O2 (g) is sealed in a container at t=200k and p=43.0 bar. Usingvarious techniques the compression factor, Z, for O2(g) in thiscontainer was determined to be 0.802a. assuming that O2...
- Q Why do mountaineers need weeks or even months to becomeacclimated before climbing summits like Mount Everest?Write the reaction of hemoglobin (Hb) with oxygen to help youanswer this question.How does that...
- Q Given the following heats of formation (ΔH°f, 25°C)and heats of combustion (ΔH°c, 25°C) data, determine theheat of reaction for the liquid-phase esterification of lactic acid(C3H6O3) with ethanol(C2H5OH) to form ethyl...
- Q A particular reaction has an activation energy,Ea, of 112 kJ/mol.  If the rateconstant for the reaction is 0.00621 s−1 at 452 °C, at what temperature(in°C)would the rate constant be 0.145 s−1?
- Q Mercury has a density of 13.6Give the symbol of an elemental metal that will float in Hg(liq) The choices are -Aluminium, Copper, Gold, Mercury, Silver, Brass, Cast Iron, 14carat gold...
- Q - A 35.0 g sample of ethylene glycol, HOCH2CH2OH is dissolved in500 g of water. The vapor pressure of water at 32 ï‚°C is 35.7 mmHg,What is the vapor pressure...
- Q What is mass (including electrons and without electrons) of oneatom of each of these elements (in grams): Chromium, Molybdenum,and Tungsten?
- Q The equilibrium constant, Kc, for the followingreaction is 41.1 at 289 K.2CH2Cl2(g)--> CH4(g) +CCl4(g)Â Â When a sufficiently large sample ofCH2Cl2(g) is introduced intoan evacuated vessel at 289 K, the equilibriumconcentration of...
- Q when compounds are nitrated, typicallya mixture of concentratednitric and sulfuric acids are required. howerever, when phenolundergoes nitration only dilute nitric acid is required. why isthis?
- Q are solid particles with long range orderA. crystalline particles.B. amorphous particlesC. rigid particlesD. regular particlesE. inelastic particles
- Q A) a scuba tank has a volume of 11.0L and is pressurized to 2975PSI. assuming temperature of 25C, what would the volume of the gasbe if it were all released...
- Q 75mL of a 0.111 mol L-1 solution of butanoicacid(H3CCH2CH2C(=O)OH), and 38 mLof a solution of KOH of molarity 0.101 mol L-1 are mixedin a 250 mL beaker. What would be...
- Q In addition to the molecular orbital treatment of H2, the groundstate can be treated by the so-called valence bond (Heitler-London)approach, where individual covalent bonds are combined to form anantisymmetric wave...
- Q Consider the following system at equilibriumN2(g)+3H2(g) <------> 2NH3(g)+ heatIndicatre which way the reaction wil shift when making thefollowing changes1. Decreasing in the temperture2. Increasing in the temperture3. Removing some of...
- Q A solution is 0.017 M in Al3+ and 0.136 M in NaF. If theKf for AlF63- is 7.0 × 10^19, what is the aluminum ionconcentration at equilibrium?
- Q Explain the relationship between group number and the number ofbonds that ions of elements are likely to form.Please explain in detial!
- Q 1.) Given the following data:C2H2(g) + 5/2 O2(g) à 2CO2(g) +H2O(l)     ΔH= -1300.kJC(s) + O2(g) à CO2(g)                                 ΔH= -394kJH2(g) + O2(g) à H2O(l)                                ΔH= -286kJUse Hess’s Law to calculate ΔH for the reaction2C(s) + H2(g)...
- Q - Why are electron withdrawing groups (ie nitro group, carbonyl)meta directors?- Why are electron donating groups o,p-directors? -Why are halogens deactivators, but o,p-directors
- Q Calculate the freezing point and boiling point of a solutioncontaining 10.6 g of naphthalene (C10H8) in 114.0 mL of benzene.Benzene has a density of 0.877 g/cm3.Calculate the freezing point of...
- Q How many grams of dipotassium oxalate (FM 166.22) should beadded to 20.0 mL of 0.800 M HClO4 to give a pHof 4.40 when the solution is diluted to 450. mL?(pKa1...
- Q How do I find the density of water using the density ofan empty graduated cylinder that weighs 86.246g and also using themass of a graduated cylinder with 10 mL of...
- Q Describe the Bohr model and describe the quantum-mechanicalmodel of the electron. What is the advantage of each model and whatis the major difference between the two models?
- Q 1. A block of an alloy of mass 27.0 g and at a temperature of277.22 K is placed in a calorimeter containing 41.0 g of water at357.74 K. If the...
- Q Write the molecular, total and net ionic equations.Potassium hydroxide +chromium(III) nitrateSodium metal + a large excess of waterPotassium perchlorate + sulfuric acidBarium hydroxide + hydrobromic acidPhosphoric acid+ magnesium chlorideHydrocyanic acid+sodium...
- Q 1. PF5 has five single bonds to the central atom. SF4 has foursingle bonds to the central atom and the central atom possesses alone pair of electrons. How can this...
- Q in a lab experiment to test the change in temperatureof NaCl and the change in temperature of water:Specific heat of NaCl is 0.88specific heat of DI water is 4.2in the...
- Q Calculate [H3O+] and [OH−] for each of the following solutionsat 25 ∘C given the pH.Part A.) pH= 8.65Part B.)  pH= 11.40Part C.)  pH= 2.94
- Q A chemist claims to have discovered a new gaseous element,effuvium (Ef), which reacts with atmospheric nitrogen to formeffuvium nitride: 2 Ef(g) + 3 N2(g) 2 EfN3(g) In a containerinitially containing...
- Q Foreach of the following unbalance chemical equation suppose thatexactly 5.00g of each reactant is taken. Determine which reactantis limiting and calculate what mass of each product is expected (assuming that...
- Q Write the summary on the Analysis of Copper using Flame atomicabsorption.Describe sources of experimental error and how it can impact thedata collected ?discuss what is matrix interference that might occur...
- Q In the citric acid cycle, malate is oxidized to oxaloacetate bythe enzyme malate dehydrogenase, which uses NAD+ as an electronacceptor. In cells, the ratio of [NAD+]/[NADH] is kept very high.Given...
- Q What do tyrosinase inhibitors do?What is the importance of tyrosinase and tyrosinase inhibitors inthe food industry?
- Q Calculate the pH of a 0.10 M solution of barium hydroxide,Ba(OH)2. Express your answer numerically using two decimalplaces.Calculate the pH of a 0.10 M solution of NaOHNaOH. Express youranswer numerically...
- Q Calculate how many mL of 0.100 HCl should be added to how manygrams of sodium acetate dihydrate (NaOAc * 2H2O, FM 118.06) toprepare 250.0 mL of 0.100 M buffer, pH...
- Q Estimate, on the basis of CTST, the pre-exponential factor at300K for the following types of gas reactions:a. a bimolecular reaction between an atom and a diatomicmolecule with the formation of...
- Q Nitrogen and hydrogen combine at high temperature, in thepresence of a catalyst, to produce ammonia.N2(g)+3H2(g)-->2NH3(g)Assume 0.210 mol N2 and 0.664 mol H2 are present initially.1.)After complete reaction, how many molecules...
- Q You are considering options for a deposition process for a-Sithat gives acceptable quality films and is able to deposit 5 nmthickness in less than a minute. Compare the HW PECVD,...
- Q * Predict solubility based on hydrogen bondinginteractionsPredict electron distribution in a bond fromelectronegativityDefine the chemical basis of hydrogen bonding.Identify and construct hydrogen bond donor and acceptorgroupsPredict hydrogen bonding potential among...
- Q How many milliliters of 0.100 M NaOH are required to neutralizethe following solutions?(a) 8.00 mL of 0.0500 M HCL(b) 20.00 mL of 0.126 M HNO3(c) 45.00 mL of 0.215 M...
- Q calculate the pH at the equivalence point of a titration of0.3326 g THAM pKa 5.92 dissolved initially in 25 mL of H2O with0.1042 M Hcl please show step by step
- Q Methanoic acid has a Ka=1.6X10-4. Calculate the pH of the finalsolution when 23.90 mL of 0.100M NaOH is added to 25.00 mL of 0.100M methanoic acid
- Q Question 1a)velocity of an electron emitted by a metal whose thresholdfrequency is 2.24×1014 s−1s−1 when it is exposed tovisible light of wavelength 5.14×10−7 mm .Find the Velocityb)What is the de...
- Q At a certain temperature and pressure an element has the simplebody-centred cubic unit cell, depicted below. The correspondingdensity is 8.597 g cm-3 and the atomic radius is 1.428 Ã…. Calculate(and...
- Q For each process, state whether ΔGsys,ΔHsys, and ΔSsys are positive, negative orzero.a. An ideal gas is compressed in one step from 1 atm to 5 atm aconstant temperature.b. Water freezes...
- Q Calculate the PH of the following solutionsa) 25g HCIO4 in 500ml aqueous solutionb) 0.2M hydrofluoric acidc) 0.02M Ca(OH)2d) 25g HCIO and 30g Ca(CIO)2 in 1000ml aqueous solution
- Q A 280.0 mL buffer solution is 0.270 M in acetic acidand 0.270 M in sodium acetate.What is the initial pH of this solution? Express your answer using two decimalplaces.What is...
- Q At 1 atm, how much energy is required to heat 55.0 g of H2O(s)at –22.0 °C to H2O(g) at 151.0 °C? Enthalpy of fusion 333.6 J/g6010. J/mol Enthalpy of vaporization...
- Q The Ka of a monoprotic weak acid is 7.84 × 10-3. What is thepercent ionization of a 0.149 M solution of this acid?
- Q 2. For the diprotic weak acid H2A, Ka1 = 2.7 × 10-6 and Ka2 =8.8 × 10-9. What is the pH of a 0.0500 M solution of H2A? What arethe...
- Q 8. Here we are going to consider the differences betweenspectra and chromatograms. A list is given below of characteristicsand behaviors of UV spectra and liquid chromatography. Somecharacteristics listed apply only...
- Q 12. Define terms system and surroundings. What does it mean tosay a system and its surroundings are in thermal equilibrium?What determines the directionality of energy transfer asheat?
- Q 1. A sludge containing 4% solid (by weight) needs to bethickened by centrifugation to ≥15% solid for disposal. Thecentrifuge has a high constant speed and produces a dewateredsludge containing 20%...
- Q Increased gaseous CO2 concentrationsare leading to decrease pH of ocean water which in turn causes harmto shellfish populations. Write all the appropriate equilibria(solubility and acid ionization) relevant to these phenomena....
- Q Calculate the equilibrium constant for the reactionS2O82-(aq) + 2 Fe2+(aq)--> 2 Fe3+(aq) + 2 SO42-(aq) at25.0°C, given that the standard cells potentials for the two halfreactions at this temperature areS2O82-(aq)...
- Q A. The freezing point of waterH2O is 0.00°C at 1atmosphere.How many grams of iron(II) nitrate(179.9 g/mol), must be dissolved in228.0 grams of water to reducethe freezing point by 0.300°C ?_____...
- Q The good chemist is tasket with determining the concentration ofmanganese for a water sample drawn from a well next to a mine. Toanalyze the sample using absorbance spectroscopy, she prepares...
- Q Calculate the pH of a 0.449 M aqueous solutionof acetylsalicylic acid (aspirin)(HC9H7O4,Ka = 3.0×10-4) and theequilibrium concentrations of the weak acid and its conjugatebase.pH=   [HC9H7O4]equilibrium=   M[C9H7O4-]equilibrium=   M
- Q 1.) Please show all worka.) Draw the reaction for imidazole, a weak base, ionizingwater. You might need to look up the structure of imidazole and becareful about where you protonate...
- Q Consider the titration of 100.0 mL of 0.100 M NaOH with1.00 M HBr. Find the pH at the following volumes of acidadded.Va = 0 mLVa = 1.0 mLVa = 5.0...
- Q For each of the following balanced chemical equations, calculatehow many moles of product(s) would be produced if 0.640mol of the first reactant were to react completely.(a) BaCl2(aq) + 2AgNO3(aq) →...
- Q When 200. mL of 0.40 M hydrochloric acid solution is mixed with3.76 g of aluminum metal, how many moles of hydrogen gas would beproduced?6HCl(aq) + 2Al(s) → 2AlCl3(aq) + 3H2(g)
- Q A concentrated solution of H2SO4 has a molarity of 15.5 M, and adensity of 1.760 g/mlA. How many grams of H2SO4 are in a liter of the solution?B. What is...
- Q A wastewater containing 150 mg/l chlorobenzene is treated in alaboratory adsorption unit using a PVC column, 1.0 inch internaldiameter, to an effluent concentration of 15 mg/l . Service times,and throughput...
Get Answers to Unlimited Questions
Join us to gain access to millions of questions and expert answers. Enjoy exclusive benefits tailored just for you!
Membership Benefits:
- Unlimited Question Access with detailed Answers
- Zin AI - 3 Million Words
- 10 Dall-E 3 Images
- 20 Plot Generations
- Conversation with Dialogue Memory
- No Ads, Ever!
- Access to Our Best AI Platform: Flex AI - Your personal assistant for all your inquiries!