Chemistry Questions and Answers April 10, 2020

The mineral trimagnesium phosphate (Mg3(PO4)2, denoted TMP) is widely used in the pharmaceutical and food industries. A pharmaceutical company needs to prepare TMP in their labs. They mix 0.5 liter MgCl2 solution (0.2 M) with 0.5 liter of 0.1 M K2HPO4 solution. In order to precipitate TMP in the required amount, the pH is controlled by either acid

What application of CHNS elemental analysers can be suggested in Food Analysis Give examples for it and explain its importance

MOX fuel uses a combination of UO2 and PuO2 in their fuel pellets. Calculate the macroscopic neutron absorption cross-section of MOX fuel load with 7w/o Pu-239. Assume all Pu present is Pu-239, with natural uranium for the remainder. Assume non 1/v behavior and use a fuel temperature of 600 deg C.

Why is it that most solidificatiodoes not begin until the temperature falls somewhat below the equilibrium melting temperature? Please give your explanations in detail based on your understanding.

Two pieces of AISI 1025 steel are being shielded-metal-arc welded with E6012 electrodes. There are some difficulties with cracking in the weld beads and in the heat affected zones. What possible corrective measures might you sugges

Two pieces of AISI 1025 steel are being shielded-metal-arc welded with E6012 electrodes. There are some difficulties with cracking in the weld beads and in the heat affected zones. What possible corrective measures might you suggest.

What are some of the attractive features of die casting compared to alternative casting methods?

Welding process may induce various impacts on the mechanical properties of the base materials depending on their initial states. Please specify the expected hardness changes around the welding pool if the base materials had been cold worked. What is the situation if they had been aging strengthened?

If excess of benzoic acid used, will the compound shown be a significant product? Why or why not? ( using a friedel crafts reaction)

OCH3 CO Ph

4G 1018 .. Vo) LT 97 epraghna.comstudent, 4 One litre of a sample of ozonized oxygen at 0C and 1 atm on passing through a KI solution, liberated iodine which required 9 ml of a thiosulphate solution. A volume of 12 ml of a 5.675 volume hydrogen peroxide solution liberated iodine from another iodide solution, which required 24 ml of the same

How much energy (in KJ) is available for sustaining muscular and nervous activity from the combustion of 1.0 mole of glucose molecules under standard conditions at 37C (body temperature) The standard entropy and enthalpy of reaction are 200 JKmol and 2808 kJmol, respectively. Backspace 78 9 4 5 6 1 2 3

The internal energy of gas is given by U 1.5 PV. It expands from 100 to 200 cm against a constant pressure of 1.0 x 10 Pa. The heat absorbed (in KJ) by the gas in the process is Backspace 7 8 9 4 5 6 1 2 3

A quantity of 8g oxygen gas is expanded isothermally at 27C from 2 dm3 to 8 dm at a constant external pressure of 4bar. If the magnitude of work done in this process is used in lifting a body of mass 40 kg, the height (in metre) upto which body can be lifted is (g 10 ms ) Backspace 7 89 4 5 6 1 2 3

A quantity of 1 g of metal carbonate was dissolved in 25 ml of normal HCI. The resulting liquid requires 50 ml of N10 caustic soda solution to neutralize it completely. The equivalent weight of metal carbonate is (A) 10 (B) 20 (C) 100 (D) 50

A volume of 25 ml of (N10) Na2CO3 solution neutralizes 10 ml of a dilute H2SO4 solution. The volume of water that must be added to 400 ml of this H2 SO4 solution in order to make it exactly N10 is (A) 1000 ml (B) 600 ml (C) 500 ml (D) 400 ml

A solution of H202 is titrated with a solution of KMNO4. The reaction is 2Mno, 5H2O2 6H 2Mn It requires 50 ml of 0.1 M KMNO4 to oxidize 10 ml of H2O2. The strength of H2O2 solution is (A) 4.25 (wv) (B) 8.5 (wv) (C) 0.85 (wv) (D) 1.7 (wv)

Household bleach contains hypochlorite ion, which is formed when chlorine dissolves in water. The determine the concentration of hypochlorite in the bleach, the solution is first treated with a Kl solution. The iodine liberated can be determined by titration with a standard thiosulphate solution. A 25 ml of certain household bleach requires 17.4

In the mixture of NaHCO, NazCO3, the volume of a given HCl required is x ml with phenolphthalein indicator and further y ml is required with methyl orange indicator. Hence, the volume of HCI for complete reaction of NaHCO present in the original mixture is (A) 2x (B) y (C) x2 (D) (y x)

xg of KHC204 requires 100 ml of 0.02 M KMnO, in acidic medium. In another experiment, y g of KHC204 requires 100 ml of 0.05 M Ca(OH),. The ratio of x and y is (A) 11 (B) 12 (C) 21 (D) 54

V mlof permanganate solution of molarity M1 reacts exactly with V2ml of ferrous sulphate solution of molarity M2, then (A) V M1 V2 M2 (B) 5V M1 V2 M2 (C) V M 5V2 M2 (D) None of these

One mol of ice is converted into water at 273K and 1 atm. The entropies of H20 (s) and H2O (1) are 38.0 and 58.0 JK mol, respectively. The enthalpy change for the conversion is (A) 5460 kJmol (B) 5460 Jmol (C) 5460 Jmol (D) 20 Jmol

The standard molar entropy of an ideal gas (y ) is 2.5 Calk mol at 25C and 1bar. The standard molar entropy of the gas at 323C and 1 bar is (In2 0.7) (A) Undefined (B) 4RIN2 (C) 5.6 calKmol (D) 8.1 calKmol

Two moles of an ideal mono atomic gas is heated from 27C to 627 C, reversibly and isochorically. The entropy of gas (A) increases by 2Rin3 (B) increases by 3R In3 (C) decreases by 2R In3 (D) decreases by 3R In3

Two moles of helium gas undergoes a cyclic process as shown in the figure. Assuming ideal behavior of gas, the magnitude of network done by the gas in this cyclic process is B 2atm Jatm 300K 400K T (A) 0 (B) 100 K In2

2 moles of an ideal mono atomic gas undergoes reversible expansion from (4L, 400K) to 8L such that TV2 constant. The change in enthalpy of the gas (A) 1500 R (B) 3000 R (C) 1500 R (D) 3000 R

One mole of monoatomic ideal gas at TK is expanded from 1L to 2L adiabatically under a constant external pressure of 1 atm. The final temperature of the gas in kelvin is (A) T T (B) (C) T 2 3x0.0821 2 (D) T 3x0.0821

to compress 16g of oxygen isothermally at 300 K from a pressure of 1.01325 x 10 Nm to 1.01325 x 10Nm is (In100 4.6, R 8.3 JKmol) (A) 5727 J (B) 11.454 KJ (C) 123.255 KJ (D) 1232.55 J

Five moles of an ideal gas is expanded isothermally from 5dm3 to 5m at 300 K. Which of the following is incorrect about the gas (A) No heat is absorbed (or) reject by the gas (B) There is no change in internal energy of the gas (C) There is no change in enthalpy of the gas (D) Pressure of the gas will be decrease by 1000 times

A system absorbs 100 KJ heat in the process shown in the figure. What is AU for the system PA 2 bar 1 bar 1m 2m (A) 50 KJ (B) 50 KJ (C) 150 KJ (D) 150 KJ

The internal energy change when a system goes from state A to B is 40 KJmol. If the system goes from A to B by a reversible path, than what would be the net change in internal energy (A) 40 KJ (B) 40 KJ (C) 40 KJ (D) Zero

Question No. 52 Maximum work can a gas do, if it is allowed to expand isothermally against (A) Vacuum (B) high pressure of surrounding (C) low pressure of surrounding (D) atmospheric pressure

Indicate which of the given electronic configurations are true ground state configurations for the respective atoms and which are false. (Take care There are some exceptions to the simple rules.) O Ca 1s22s22p63s23p64s2 true false 1s2s2p5 O Hg Xe4f145d106s2 true false O Si 1s22s22p63s23p2 O P 1s22s2p63s3d3 false

By what factor would a scuba divers lungs expand if she ascended rapidly to the surface from a depth of 134.5 ft without inhaling or exhaling If an expansion factor greater than 1.65 causes lung rupture, how far could she safely ascend from 134.5 ft without breathing Assume constant temperature (d of seawater 1.01 gml d of Hg 13.456 gmL). Hint

By what factor would a scuba divers lungs expand if she ascended rapidly to the surface from a depth of 134.5 ft without inhaling or exhaling If an expansion factor greater than 1.65 causes lung rupture, how far could she safely ascend from 134.5 ft without breathing Assume constant temperature (d of seawater 1.01 gml d of Hg 13.456 gmL). Hint

a Click on the alcohol that is primary. OH OH OH (CHshCOH b Click on the alcohol that is secondary. OH OH (CHshCOH Correct C Click on the alcohol that is tertiary. OH (CHiCOH

3. An aluminum slab of 10 20.5m has a hydrogen content of 015 ccsTp100 g of metal. a) Compute the total volume of pores if equilibrium conditions until the end of solidification are assumed. b) What is the corresponding fraction of porosity Perform this calculation for two alloys, Al7wtSi and Al4wtMg, using the solubilities given in Fig.1. Pure

USE A SEPARATE PAPER TO ANSWER THIS QUESTION. Upload it in the folder Exam 3 Mechanismunder the Assessments then Assignments tab in iCollege, within 10 minutes after you submit your multiple choice exam. Late submissions will not be accepted Write a detailed mechanism for the following reaction. Include the slow and fast steps. Draw the structures

Paragraph The measure of disorder used in thermodynamics is called entropy. The entropy of an isolated system tends to increase. Increase of entropy of universe is the driving force of spontaneous processes. Q Helium gas present in thermally insulated system at 10 atm 1L and 30OK is expanded very slowly till final pressure becomes 1atm. Find the

Paragraph The measure of disorder used in thermodynamics is called entropy. The entropy of an isolated system tends to increase. Increase of entropy of universe is the driving force of spontaneous processes. Q Which of the following is nonspontaneous under normal conditions of pressure and temperature (A) Expansion of gas (B) Dissolution of Nacl

Paragraph A 3.0 g sample containing FezO4, Fe203 and an inert impure substance is treated with excess of KI solution in presence of dilute H2SO4. The entire iron is converted to Fe2 along with the liberation of iodine. The resulting solution is diluted to 100 mL. A 20 mL of dilute solution requires 11.0 mL of 0.5 M Na,S203 solution to reduce the

How many of the following statement(s) isare correct i) All irreversible processes are spontaneous. ii) An endothermic reaction may be spontaneous at high temperatures. iii) A spontaneous process is the one which occurs without any initiation. iv) An exothermic reaction may become nonspontaneous at a particular temperature. v) For a spontaneous

A piece of zinc of mass 5.0 g is dropped into a beaker of excess dilute hydrochloride acid. Calculate the magnitude of work done (in J) as a result of the reaction. The atmospheric pressure is 1.1 atm and temperature 23 C. Given Zn 65 u, R 0.082, 1L atm 101 J Backspace 7 8 9 45 6

When q amount of heat is given to one mole of a monoatomic gas, it does q2 amount of work on surroundings. Find the heat capacity of the system in J K mol. Take R 8.314 JKmol Backspace 7 89 4 56 1 2 3

Enthalpy of vaporization of a liquid is 30 kJ and its normal bolling point is 300 K. Calculate the third law entropy (in JKmol) of the substance at 350 K, when 1 mole of the liquid at 300 K is heated to 350 K. Cp,m for the vapour from 300 K to 350 K at 1 atm is 50 JKmol. (Given In1.1670.1544 Backspace 7 8 9 4 5 6

3.0 g sample of bleaching powder is dissolved in 100 mL water. 20 mL of this suspension is acidified with HCl and treated with excess KI. The l2 liberated exactly requires 15.21 mL of 0.1 Na,S203 for complete reduction. Percentage available chlorine in the sample of bleaching powder is Backspace 7 89 4 5 6

A 50 ml 1.92 (wv) solution of a metal ion Mnt (atomic weight 60) was treated with 5.332g hydrazinehydrate (90 pure) and the mixture was saturated with CO2 gas. During this process entire metal gets precipitated as a complex M(H,N NHCO0),). The complex was filtered off and the filtrate was titrated with M KIO, in the presence of conc. HCl

Which of the following statement(s) isare correct and are linked to second law of thermodynamics (A) There exists a natural asymmetry between converting heat to work and work to heat. (B) A natural process in an isolated system is always accompanied by an increase in entropy. (C) It is impossible to convert all the heat absorbed into work

Consider a twophase system that consists of liquid water in equilibrium with water vapour kept in a constant temperature bath. The volume of the system is increased reversibly, holding T and P constant allowing some liquid to vaporize. Which of the following is correct for this process () 0 (B) ASsystem 0 (C) AStotal 0 (D AG 0

The concentration of an aqueous solution of NaOCl can be determined by a redox titration with iodide ion in an acidic solution Oct 21 2H Ct I Assume that the concentration of iodide ions in the burette is 0.12 M and the volume of iodide solution in the burette and the volume of solution taken in the flask are identical. Correct combination of

The normal boiling point of a liquid X is 400 K. which of the following statement is true about the process X (1) X (g) (A) At 400K and 1 atm pressure AG 0 (B) At 400K and 2 atm pressure AG ve (C) At 400K and 0.1 atm pressure AG ve (D) At 410 K and 1 atm pressure AG ve

Which of the following are correct (A) If 0 for real gas need not be 0. then OP (B) For a reversible reaction at equilibrium, the entropy of the system is maximum while that of the surrounding is minimum. (C) When one mole of an ideal gas is compressed to half of its initial volume and simultaneously heated to twice its initial temperature the

The correctly matched indicator(s) for the given titrations isare (A) Fe vs K2Cr20, diphenylamine (B) l2 vs Thio iodineself indicator (C) NAHCO, vs HCI methyl orange (D) Oxalic acid vs KMNO4 KMNO4 self indicator

Balance a ration for a milking dairy cow to contain CP 16 Ca .66 P .41 27 Corn Silage Feed Feed Feed 23 Alfalfa 5 Brewers Grains Feed 3 Whole Cotton Seed Leave 2 slack space for Vitamins Minerals and include .5 salt .1 VitTM mix Check the ration for K and S. Requirement is 1.0 K and 0.2 S. KCl has 50 K and NH4SO4 has 24 S Use corn and

(a)At 0 o C, liquid water and ice are in equilibrium at standard pressure, so they have the SAME molar Gibbs energy. When raise from 1.0 bar to 100 bar, how much Gibbs free energy change in the liquid phase ? (molar mass of water 18 g mol -1 ; mass density of ice = 0.9150 g cm -3 ; mass density of liquid water, 0.9999 g cm -3 ) Set the initial

1. Determine whether the molecule below is Phenol CI CI CI CI Bisphenol Biguanide Heavy metal Phenolic H CI OH CI Aldehyde (c) Hexachlorophene Gaseous Quaternary ammonium compound (quat) HIC

An object with a surface area of 85.5 cm2 is to be plated with nickel. A current of 7.95 A is applied to a solution containing nickel in the 2 oxidation state. Calculate the time required to coat the object with an even layer of nickel that is 7.51 x 103 cm thick. The density of nickel is 8.91 gcm. time S

Glutamine amidotransferases require ATP hydrolysis to make the ________ of glutamine biosynthetically active.

c) Polymerization of 1,3hexadiene can yield in either cis (Z) or trans (E) polymer. On the other hand, the polymerization of 1,4hexadiene will not have any isomer. Why (10 pts)

Be sure to answer all parts. Tris tris(hydroxymethyl)aminomethane is a common buffer for studying biological systems. (K, 5.01 x 109 and pK, 8.3) 3D (a) Calculate the pH of the Tris buffer after mixing 11.0 mL of 0.20 M HCI solution with 25.0 mL of 0.10 M Tris. (b) This buffer was used to study an enzymecatalyzed reaction. As a result of the

1. What spectral features allow you to differentiate the product from the starting material? Mass Spec: IR: H NMR: C NMR:

Copper(I) ions in aqueous solution react with NH, (aq) according to Cu(aq) 2 NH,(aq) Cu(NH, ) (aq) Kf 6.3 x 1010 Calculate the solubility (in gL) of CuBr(s) (Ksp 6.3 x 109) in 0.71 M NH, (aq). solubility of CuBr(s) gL ,The formation constant of M(CN)4 is 7.70 1016, where M is a generic metal. A 0.170 mole quantity of M(N03)2 is added to a

Rafarences) Show how could you prepare the following cyclohexenone by combining a Stork enamine reaction with an intramolecular aldol condensation by drawing the appropriate pyrrolidine enamine and enone precursors. CH,

Breakdown of disaccharides to monosaccharides occurs small intestine lumen O mouth O stomach

Assign an IUPAC name for the following molecule.

Some measurements of the initial rate of a certain reaction are given in the table below. H, 1 L initial rate of reaction 1.17 M 1.05 M 0.962 Ms 0.133 M 1.0S M 0.109 Ms 1.17 M 0.278 M 0.255 Ms Use this information to write a rate law for this reaction, and calculate the value of the rate constant k. Round your value for the rate constant to 3

1) Despite the radical increase in the use of plastics over the last few decades, the mass of plastics at landfills stayed pretty much the same. Which statement explains this contradicting phenomenon? a) The mass of plastic at landfills has not changed because there are less plastic products on the market. b) The mass of plastic at landfills has

Shown below are the four molecular orbital functions, 1-4, for cyclic H4, expressed in terms of the hydrogen 1s atomic functions, i (i = 1 - 4). 1 = N1 (1 + 2 + 3 + 4) 2 = N2 (1 3) 3 = N3 (2 4) 4 = N4 (1 2 + 3 4) Sketch an MO energy level diagram (reference to in units of ) for the cyclic H4, and determine the total energy (relative to

Question 9 10 A solution of a nonvolatile nonelectrolyte, 0.5 g, is dissolved in 100 mL of water. When the solution is placed on the opposite side of a semipermeable membrane, with pure water on the other side, the side with the solution goes up 5.6 cm because of the osmotic pressure. Mercury has a density of 13.6 gmL. What is the osmotic

Construct the titration curve for the titration of 12.0 ml of 0.060 M HCN (k, 4.9 x10 10 with 0.120 M KOH solution. (Hint you need to upload your graph on the exam document to get any points. Make sure to show your data and calculations. you need to show your initial value, 34 values before the equivalence point, at the equivalence point, 3 4

A 1.058g sample of a copper unknown was dissolved in water and diluted to a final volume of 100.0 mL. The sample was analyzed using a UVVIS spectrophotometer and the absorbance was found to be 0.529. The calibration curve gave a best fit line of A 8.58 M. Calculate the (ww) Cu in the sample. Give your answer to one place after the decimal. Do not

QUESTION 6 A hypothetical metal ion M forms a 11 stable complex with EDTA and the re 321 constant is equal to 10 Mat pH 13.17 (this is the pH at which the titration Using this information, answer the following questions Calculate the free uncomplexed concentration of the metal ion M at the equivalence point when the complexometric titration is

2. Suppose that an energy of 500 kJ mol is available in a collision but 300 kJ mol is needed to break a particular bond in a molecule with s 12. Use the RRK model to calculate the steric Pfactor.

C9H15O4 i want the IR spectrum and C13 NMR and H NMR ???

Chemistry 1A Name Quantum Theory Periodic Trends 1. What element is represented by the electron configuration 1s 2s 2p3s3p4s 3d 2. What element is represented by the orbital diagram 1s 2s 2p 3. Draw the orbital diagrams (boxline notation) for the following species Mn2 Cu 4. Write the electron configuration for the following elements and ions

Which of the structures below is (4R)-4ethyl-2,4- dimethylcyclohexan-1-one?

a. b. .... d. A A O B B. O C C O D D

Determine whether the following statement regarding the mechanism of the SERCA pump is TRUE (T) or FALSE (F). 1. In the E1 conformation, the two Ca 2+ -binding sites are exposed on the luminal side of the ER or sarcoplasmic reticulum. 2. ATP binding alone drives a conformation change from E1 to E2.

Keq for this reaction is 56. Determine the concentration at equilibrium if you start with 2.3 grams of Hydrogen and 200 grams of Iodine in a 2.3 liter container. If you now add an extra .25M of H 2(g) after equilibrium, calculate Q c. Recalculate now what the concentrations should be at equilibrium. H 2 (g) + I 2(g) 2HI (g ) Kc = 56

a) A solution is made by mixing 350 mL of .5 M hydrofluoric acid with 50 mL of 1.5 M KOH. Calculate the pH of the solution. (b) to the solution above is added 2.00 grams of sodium fluoride. What is the new pH? (c) to the solution from part (a) you add 75 mL of .5 M HCl. What is the new pH? (d) To the solution from part (a) you add 25 mL of .45 M

Determine the value of AG for the reaction 2NO,(2)N,0,(2) given AH (kJimol) S (J(mol K)) Substance 33.2 240.0 NO,(g) N,0,1g) 9.2 304.2 Select one a. 52.3 kJ b.43 kJ X C. 4.8 kJ d. 52.3 kJ e.4.8 kJ The correct answer is 4.8 kJ

synthesis of p-nitroaniline from acetanilide

Why was ammonium hydroxide used during the pnitroaniline experiment O to make the mixture acidic, thereby precipitating the product O to make the mixture basic, thereby precipitating the product O to make the mixture basic, thereby causing the product to be water soluble O to neutralize the HNOH,SO, mixture

How are the para and ortho isomers of nitroaniline separated O distillation O recystallization O reflux O filtration Question 3 Which would be a suitable solvent for the luminol reaction O water (BP100C) O glycerol (BP290C) O methylene chloride (BP40C) O ethanol (BP79C)

What was used to catalyze the luminol reaction O potassium ferracyanide O hydrazine acetic acid O hydrogen peroxide

Which compound would not react with 1,6hexanediamine to give a polymer O diketone O all would react O dicarboxylic acid O diacyl chloride