95 + Interview Questions in Moles in Basic Chemical Engineering Page 2 InterviewSolution

51.	10 Kg/s of a fluid with density 10 Kg/m^3 is passed into a tank of capacity 50 m3, how much time will it take to fill the tank?(a) 5 Second(b) 50 Second(c) 500 Second(d) 5000 SecondI had been asked this question during an interview.This key question is from Flow Rate in portion Moles, Density & Concentration of Basic Chemical Engineering
Answer» The correct ANSWER is (b) 50 SECOND Best EXPLANATION: Flow rate of fluid = 10/10 = 1 m^3/s, => Time = 50/1 = 50 second.

Discussion

52.	A Composition of carbon dioxide, oxygen and nitrogen with mole ratio 1:2:5 with 4 moles of oxygen, enters a reactor with a flow rate of 100 kg/s, the ratio of rates of leaving the reactor of the three is 5:2:1, and 5 moles of nitrogen leaves the reactor, what is the total number of moles leaving the reactor?(a) 6.1(b) 6.2(c) 6.3(d) 6.4The question was posed to me in an interview.Enquiry is from Flow Rate topic in chapter Moles, Density & Concentration of Basic Chemical Engineering
Answer» Correct answer is (B) 6.2 The explanation: number of moles of carbon dioxide, oxygen and nitrogen are 2, 4 and 10 respectively, let the LEAVING flow rates of carbon dioxide, oxygen and nitrogen are 5y, 2y and y respectively, => for nitrogen, 10100 = y5 => y = 200 kg/s, => for oxygen, 4100 = 400n => n = 1, for carbon dioxide, 2100 = 1000n => n = 0.2, => TOTAL number of moles leaving the reactor = 5 + 1 + 0.2 = 6.2.

Discussion

53.	10 moles of oxygen divides and enters two reactors flow rate 45 kg/s and leaves the reactors at the flow rates of 6 kg/s and 9 kg/s, what are number of moles of oxygen that leaves the reactor with 9 kg/s?(a) 180(b) 450(c) 60(d) 90The question was posed to me by my school teacher while I was bunking the class.I need to ask this question from Flow Rate in division Moles, Density & Concentration of Basic Chemical Engineering
Answer» The correct ANSWER is (d) 90 The best explanation: Let number of moles entering and leaving the second reactor be n1 and n2 RESPECTIVELY, applying reaction equilibrium equation to WHOLE system, => 1045 = N(6 + 9), => n = 30, => Applying reaction equilibrium equation to both the reactors separately, => n145 = n29 => n2 = 5n1, and (10 – n1)45 = (30 – n2)6, Solving both equations we get n2 = 90.

Discussion

54.	A liquid of density 0.1 kg/m^3 is flowing through a pipe at a rate of 15 kg/s, what will be the area of the pipe if the fluid velocity is 5 m/s?(a) 30 m^2(b) 45 m^2(c) 75 m^2(d) 90 m^2The question was posed to me in a job interview.The above asked question is from Flow Rate in chapter Moles, Density & Concentration of Basic Chemical Engineering
Answer» Right ANSWER is (a) 30 m^2 To explain: Volumetric FLOW rate of the liquid = 15/0.1 = 150 m^3/s, => Area of pipe = 150/5 = 30 m^2.

Discussion

55.	A liquid is flowing through a pipe of cross section 4 m^2 at a rate of 4 kg/s, at a point pipe is divided into two pipes of areas of equal areas, what will be the ratio of flow rate in both the pipes?(a) 1:3(b) 1:1(c) 1:2(d) 2:3I have been asked this question during an internship interview.This intriguing question comes from Flow Rate topic in chapter Moles, Density & Concentration of Basic Chemical Engineering
Answer» CORRECT choice is (b) 1:1 Easiest explanation: Since AREAS of the pipes are EQUAL, by CONTINUITY equation flow will divide EQUALLY in the pipes, so their ratio will be 1:1.

Discussion

56.	The velocity of water in a pipe of area 5 m^2 is 10 m/s, what will be the flow rate of water?(a) 25 m^3/s(b) 50 m^3/s(c) 75 m^3/s(d) 100 m^3/sI got this question in an international level competition.This key question is from Flow Rate topic in portion Moles, Density & Concentration of Basic Chemical Engineering
Answer» The correct option is (B) 50 m^3/s To ELABORATE: Flow rate = AREAVELOCITY = 510 = 50 m^3/s.

Discussion

57.	What is the volumetric flow rate if 100 kg of water is collected in 10 seconds? (Density of water = 1000 kg/m3)(a) 0.1 m^3/s(b) 0.2 m^3/s(c) 0.01 m^3/s(d) 0.02 m^3/sThe question was asked by my college director while I was bunking the class.My question is from Flow Rate topic in division Moles, Density & Concentration of Basic Chemical Engineering
Answer» Right option is (c) 0.01 m^3/s To explain: VOLUME of WATER collected = 100/1000 = 0.1 m^3, => volumetric FLOW rate = 0.1/10 = 0.01 m^3/s.

Discussion

58.	Which of the following is not conserved for the flow of an incompressible liquid in a pipe with variable area?(a) Mass(b) Volume(c) Velocity(d) Flow RateThe question was posed to me in a job interview.The origin of the question is Flow Rate in chapter Moles, Density & Concentration of Basic Chemical Engineering
Answer» CORRECT answer is (C) Velocity The best I can explain: According to the equation of CONTINUITY, the product of area and velocity REMAINS constant throughout the pipe, since the area of the pipe is VARIABLE, so the velocity if the liquid is variable.

Discussion

59.	What is the mass flow rate of a liquid flowing through a pipe of which 100 grams of water was collected in 10 seconds?(a) 0.01 kg/s(b) 0.05 kg/s(c) 0.1 kg/s(d) 0.5 kg/sI have been asked this question in an online quiz.The doubt is from Flow Rate topic in chapter Moles, Density & Concentration of Basic Chemical Engineering
Answer» Correct choice is (a) 0.01 kg/s The best EXPLANATION: MASS flow RATE = 0.1/ 10 = 0.01 kg/s.

Discussion

60.	What is the specific gravity of N2 at 27oC and 6 Pa with respect to 0.1 Kg/m^3?(a) 0.16(b) 0.33(c) 0.51(d) 0.89I have been asked this question in an online quiz.The query is from Specific Gravity in chapter Moles, Density & Concentration of Basic Chemical Engineering
Answer» CORRECT option is (b) 0.33 Easiest explanation: SPECIFIC GRAVITY = (614/8.314300)/0.1 = 0.33.

Discussion

61.	Which of the following is the unit of flow rate?(a) Kg/s(b) Liters/s(c) Moles/s(d) All of the mentionedThe question was posed to me by my school teacher while I was bunking the class.I'm obligated to ask this question of Flow Rate topic in chapter Moles, Density & Concentration of Basic Chemical Engineering
Answer» The correct choice is (d) All of the mentioned For explanation I WOULD say: Mass flow RATE = m/t, => UNIT = kg/s, VOLUMETRIC flow rate = V/t, => unit = Liters/s, molar rate = n/t, => unit = moles/s.

Discussion

62.	What is the specific gravity of O2 at 27oC and 60 Pa with respect to 1 Kg/m^3?(a) 0.15(b) 0.28(c) 0.54(d) 0.76The question was asked in an internship interview.I would like to ask this question from Specific Gravity topic in division Moles, Density & Concentration of Basic Chemical Engineering
Answer» CORRECT option is (d) 0.76 Easy explanation: SPECIFIC gravity = (6032/8.314300)/1 = 0.76.

Discussion

63.	What is the specific gravity of 10 Kg of water occupied in 5 m3 with respect to 100 g/m^3?(a) 1(b) 5(c) 10(d) 20This question was addressed to me during an online interview.This question is from Specific Gravity topic in portion Moles, Density & Concentration of Basic Chemical Engineering
Answer» CORRECT CHOICE is (d) 20 For explanation I would say: SPECIFIC GRAVITY = (10/5)/0.1 = 20.

Discussion

64.	What is the specific gravity of 5 Kg of water occupied in 10 m3 with respect to 500 g/m^3?(a) 0.5(b) 1(c) 2(d) 5I got this question during an online exam.Enquiry is from Specific Gravity in division Moles, Density & Concentration of Basic Chemical Engineering
Answer» The CORRECT OPTION is (B) 1 To elaborate: SPECIFIC GRAVITY = (5/10)/0.5 = 1.

Discussion

65.	Mass of a substance is changing with respect to its volume as m = -v^3 + 3v^2 -2v, what is the maximum specific gravity of the substance between v = 1 m^3 and v = 2 m^3? (Density of reference substance = 0.25 kg/m^3)(a) 1(b) 2(c) 3(d) 4I have been asked this question during a job interview.The query is from Specific Gravity in chapter Moles, Density & Concentration of Basic Chemical Engineering
Answer» Right option is (a) 1 The explanation: Density of substance D = m/V = -v^2 + 3v – 2, => Specific GRAVITY of substance S = D/0.25 = 4(-v^2 + 3v – 2), => dS/dv = 4(-2v + 3) = 0, => v = 1.5, => S is maximum at v = 1.5, => maximum specific gravity = 4(-1.5^2 + 3*1.5 – 2) = 1.

Discussion

66.	What is the average mass of a substance with specific gravity 10, and its volume varies with time as V = t/500, from t = 2, to t = 0 seconds? (Density of water = 1000 kg/m^3)(a) 25(b) 20(c) 40(d) 75I had been asked this question during an online exam.This is a very interesting question from Specific Gravity topic in section Moles, Density & Concentration of Basic Chemical Engineering
Answer» Correct answer is (B) 20 The BEST explanation: Density of substance = 10 * 1000 = 10000 kg/m^3, => mass of substance = 10000*t/500 = 20t, => AVERAGE mass = (1/2)∫20t = 5t^2 = 5(2^2 – 0^2) = 20.

Discussion

67.	What is the specific gravity of 10 Kg of water occupied in 10 m3 with respect to 200 g/m^3?(a) 0.2(b) 0.5(c) 1(d) 5I have been asked this question during an interview.My question comes from Specific Gravity in division Moles, Density & Concentration of Basic Chemical Engineering
Answer» The CORRECT answer is (d) 5 The best I can explain: Specific gravity = (10/10)/0.2 = 5.

Discussion

68.	What is the API gravity of a substance with specific gravity 1?(a) 131.5(b) 141.5(c) 10(d) 50I have been asked this question in semester exam.My doubt is from Specific Gravity in portion Moles, Density & Concentration of Basic Chemical Engineering
Answer» Right choice is (c) 10 To EXPLAIN I would SAY: API = (141.5/sp.gr) – 131.5 = 141.5/1 – 131.5 = 10.

Discussion

69.	What is the mass of a cone of radius 1 m and height 3 m having specific gravity 0.1? (Density of water = 1000 kg/m^3)(a) 314.16 kg(b) 425.24 kg(c) 136.16 kg(d) 325.24 kgThis question was posed to me in a national level competition.The above asked question is from Specific Gravity in division Moles, Density & Concentration of Basic Chemical Engineering
Answer» CORRECT choice is (a) 314.16 KG The explanation is: VOLUME of cone = (1/3) π1^23 = 3.1416 m^3, DENSITY of cone = 0.11000 = 100 kg/m^3, => MASS of cone = 100*3.1416 = 314.16 kg.

Discussion

70.	API gravity is necessary for the calculation of specific gravity of petroleum products, because(a) Volume of the petroleum products changes with temperature(b) Mass of petroleum products changes with temperature(c) Potential energy of petroleum products changes with temperature(d) None of the mentionedI have been asked this question in an interview for job.This interesting question is from Specific Gravity topic in section Moles, Density & Concentration of Basic Chemical Engineering
Answer» Right choice is (a) VOLUME of the petroleum products changes with temperature The BEST I can explain: Since volume of petroleum products changes significantly with temperature, that means DENSITY of petroleum products changes significantly with temperature, so that’s why specific gravity of petroleum products changes with temperature, and that’s why API gravity is REQUIRED.

Discussion

71.	API gravity is measured in,(a) Gravity meter scale(b) Hydrometer scale(c) Richer scale(d) None of the mentionedThe question was asked during an interview.Question is from Specific Gravity topic in division Moles, Density & Concentration of Basic Chemical Engineering
Answer» Right option is (B) HYDROMETER SCALE To explain: API GRAVITY is measured in Hydrometer scale.

Discussion

72.	What is the specific gravity of a substance with mass 10 kg and volume 2 m^3, with respect to the reference density 50 g/m^3?(a) 0.1(b) 0.2(c) 0.3(d) 0.4The question was asked in class test.I'm obligated to ask this question of Specific Gravity in division Moles, Density & Concentration of Basic Chemical Engineering
Answer» Right CHOICE is (a) 0.1 Explanation: Density of the SUBSTANCE = 10/2 = 5 kg/m^3, => SPECIFIC GRAVITY = 5/50 = 0.1.

Discussion

73.	It is necessary to mention the temperature at which specific gravity is calculated, because(a) Mass of the substance changes with temperature(b) Rigidity of the substance changes with temperature(c) Density of the substance changes with temperature(d) None of the mentionedThe question was asked in a job interview.My query is from Specific Gravity in division Moles, Density & Concentration of Basic Chemical Engineering
Answer» The correct CHOICE is (c) Density of the substance changes with TEMPERATURE Explanation: Since the VOLUME of the substance changes with temperature, which means density of the substance changes with temperature, that’s why it is required to mention the temperature at which specific GRAVITY is calculated.

Discussion

74.	What is the specific gravity of a substance with density 100 kg/m^3 with respect to reference substance of density 100 lb/m^3?(a) 1.1(b) 2.2(c) 3.3(d) 4.4I have been asked this question during a job interview.The origin of the question is Specific Gravity topic in division Moles, Density & Concentration of Basic Chemical Engineering
Answer» Right ANSWER is (B) 2.2 To ELABORATE: Density of the SUBSTANCE = 1002.2 = 220 lb/m^3, Specific gravity = (1002.2)/100 = 2.2.

Discussion

75.	A cylinder completely filled with water has density = 10 kg/m^3 and volume 5 m^3 , now a cube with side 1 m and density 25 kg/m^3 is dipped into the cylinder with some water dropping out, what is the final density of cylinder?(neglect the mass of cylinder)(a) 13 kg/m^3(b) 15 kg/m^3(c) 17 kg/m^3(d) 19 kg/m^3I had been asked this question in a job interview.Question is from Density topic in chapter Moles, Density & Concentration of Basic Chemical Engineering
Answer» Right CHOICE is (a) 13 kg/m^3 Easy explanation: Initial mass of cylinder = 105 = 50 kg, mass of cube = 251 = 25 kg, => mass of water coming out = 10*1 = 10 kg, => FINAL DENSITY of cylinder = (50 + 25 – 10)/5 = 13 kg/m^3.

Discussion

76.	An empty vessel has with mass 5 kg with volume 0.1 m^3, is now completely filled with a liquid of density 100 kg/m^3, what is the final density of the cylinder?(a) 50 kg/m^3(b) 100 kg/m^3(c) 150 kg/m^3(d) 200 kg/m^3This question was addressed to me by my school principal while I was bunking the class.My question comes from Density topic in division Moles, Density & Concentration of Basic Chemical Engineering
Answer» RIGHT CHOICE is (c) 150 kg/m^3 Easiest explanation: MASS of LIQUID = 100*0.1 = 10 kg, => total mass of cylinder = 10 + 5 = 15 kg, => FINAL density of liquid = 15/0.1 = 150 kg/m^3.

Discussion

77.	What is the unit of specific gravity?(a) Kg/m^3(b) N/m^3(c) m/s^2(d) DimensionlessI had been asked this question during an interview.My enquiry is from Specific Gravity topic in chapter Moles, Density & Concentration of Basic Chemical Engineering
Answer» The correct answer is (d) DIMENSIONLESS The explanation: SPECIFIC GRAVITY of a SUBSTANCE is the ratio of density of the substance and density of a REFERENCE substance, so it is dimensionless.

Discussion

78.	What is the mass of a cube having surface area 24 m^2, and density 1 kg/m^3?(a) 1 kg(b) 2 kg(c) 4 kg(d) 8 kgThe question was posed to me in an internship interview.My question is taken from Density topic in division Moles, Density & Concentration of Basic Chemical Engineering
Answer» Correct answer is (d) 8 kg The best I can explain: SIDE of the cube = (24/6)^0.5 = 2 m, => MASS of cube = 1*2^3 = 8 kg.

Discussion

79.	What is the mass of a liquid having density 20 kg/m^3, enclosed in a sphere of radius 1 m?(a) 80.7 kg(b) 83.7 kg(c) 85.7 kg(d) 88.7 kgI got this question in an online interview.My query is from Density in section Moles, Density & Concentration of Basic Chemical Engineering
Answer» RIGHT answer is (b) 83.7 kg To EXPLAIN I would say: Volume of LIQUID = (4/3)π1^3 = 4.18 m^3, => mass of liquid = 20*4.18 = 83.7 kg.

Discussion

80.	What is the density of a liquid of mass 20 kg, enclosed in a cuboid of surface areas of three sides as 1 m^2, 2 m^2, 5 m^2, and one of its sides is 2 m?(a) 1 kg/m^3(b) 2 kg/m^3(c) 3 kg/m^3(d) 4 kg/m^3I got this question at a job interview.Question is taken from Density topic in chapter Moles, Density & Concentration of Basic Chemical Engineering
Answer» Right answer is (b) 2 kg/m^3 Explanation: Sides of the cuboid are 1m, 2m and 5m, => VOLUME = 10 m^3, DENSITY = 20/10 = 2 kg/m^3.

Discussion

81.	What is the density of a liquid of mass 10 kg and contained in a cylinder of radius 5 m and surface area (excluding top and bottom) of 10π m^2?(a) 0.2π kg/m^3(b) 0.4π kg/m^3(c) 0.5π kg/m^3(d) 0.6π kg/m^3I have been asked this question in examination.This intriguing question originated from Density in chapter Moles, Density & Concentration of Basic Chemical Engineering
Answer» Right choice is (B) 0.4π kg/m^3 The explanation: HEIGHT of cylinder = 10π/(2π*5) = 1 m, => VOLUME of cylinder = π(5^2)1 = 25π, => density of liquid = 10/25π = 0.4π kg/m^3.

Discussion

82.	A liquid of mass 10 kg is enclosed in a cylinder of radius 1 m and length 5 m, what is the density of liquid?(a) 0.54 kg/m^3(b) 0.44 kg/m^3(c) 0.63 kg/m^3(d) 0.83 kg/m^3The question was asked in examination.Query is from Density topic in portion Moles, Density & Concentration of Basic Chemical Engineering
Answer» The CORRECT OPTION is (c) 0.63 kg/m^3 The best explanation: Volume of CYLINDER = π(1^2)5 = 5π m^3, => Density = 10/5π = 0.63 kg/m^3.

Discussion

83.	A solid of density d is dropped in a liquid of density D, if d>D then,(a) Solid will completely sink(b) Solid will completely float(c) Solid will partially sink(d) None of the mentionedI had been asked this question in an internship interview.Query is from Density topic in division Moles, Density & Concentration of Basic Chemical Engineering
Answer» RIGHT choice is (a) SOLID will completely sink Easiest explanation: SINCE the density of solid is GREATER than that of liquid, this means that the WEIGHT of the solid will be higher than its buoyancy force so it will completely sink.

Discussion

84.	Which of the following is not a unit of density?(a) Kg/m^3(b) N/m^3(c) N.s^2/m^4(d) g/cm^3This question was addressed to me in an online quiz.This interesting question is from Density topic in division Moles, Density & Concentration of Basic Chemical Engineering
Answer» Right option is (b) N/m^3 To ELABORATE: Dimensions of DENSITY are M^1L^-3, which is not the DIMENSION of N/m^3, so N/m^3 is not the unit of density.

Discussion

85.	What is the density of a substance of mass 10 grams and volume 5 liters?(a) 2 kg/m^3(b) 20 kg/m^3(c) 200 kg/m^3(d) 2000 kg/m^3The question was asked during an internship interview.I'm obligated to ask this question of Density in division Moles, Density & Concentration of Basic Chemical Engineering
Answer» The CORRECT CHOICE is (a) 2 kg/m^3 To EXPLAIN: Density = (1010^-3)/(510^-3) = 2 kg/m^3.

Discussion

86.	What are the number of moles of hydrogen in NH4[Cr(SCN)4(NH3)2] if the weight of nitrogen in it is 49 grams?(a) 3.5(b) 5(c) 7(d) 10I got this question in a national level competition.Origin of the question is The Mole topic in section Moles, Density & Concentration of Basic Chemical Engineering
Answer» The correct choice is (B) 5 For EXPLANATION I WOULD SAY: Moles of nitrogen = 49/14 = 3.5, => moles ofNH4[Cr(SCN)4(NH3)2] = 3.5/7 = 0.5, => moles of hydrogen = 0.5*10 = 5.

Discussion

87.	What are the number of molecules of water in CuSO4•5H2O, if the weight of oxygen in it is 36 grams?(a) 3.25 X 10^23(b) 5.25 X 10^23(c) 7.52 X 10^23(d) 9.52 X 10^23I got this question during an interview.Question is taken from The Mole in division Moles, Density & Concentration of Basic Chemical Engineering
Answer» Right choice is (C) 7.52 X 10^23 The best I can explain: NUMBER of moles of oxygen = 36/16 =2.25, => number of moles of CuSO4•5H2O = 2.25/9 = 0.25, => number of molecules of water = 0.255(6.022 X 10^23) = 7.52 X 10^23.

Discussion

88.	What are the number of moles of nitrogen in 274 grams of (NH4)2Ce(NO3)6?(a) 16(b) 8(c) 6(d) 4This question was addressed to me during an interview.This intriguing question originated from The Mole topic in portion Moles, Density & Concentration of Basic Chemical Engineering
Answer» RIGHT choice is (d) 4 The EXPLANATION is: Molecular Weight of (NH4)2Ce(NO3)6 = 548 grams, => MOLES of (NH4)2Ce(NO3)6 = 274/548 = 0.5, => number of moles of NITROGEN = 0.5*8 = 4.

Discussion

89.	Which of the following has the same number of moles as in 398 grams of CuSO4?(a) 2 grams of hydrogen(b) 40 grams of oxygen(c) 35 grams of nitrogen(d) 58.5 grams of Sodium chlorideI had been asked this question by my college professor while I was bunking the class.Asked question is from The Mole topic in chapter Moles, Density & Concentration of Basic Chemical Engineering
Answer» The correct option is (b) 40 grams of OXYGEN The explanation is: NUMBER of moles of CuSO4 = 398/ 159 ≈ 2.5, and number of moles of oxygen = 40/16 = 2.5.

Discussion

90.	What are the number of moles of Hydrogen in 158 grams of Ammonium Bicarbonate?(a) 5(b) 10(c) 15(d) 20I had been asked this question in examination.My question is from The Mole topic in chapter Moles, Density & Concentration of Basic Chemical Engineering
Answer» Right answer is (B) 10 Explanation: MOLECULAR Weight of ammonium BICARBONATE (NH4HCO3) = 79 grams, => MOLES = 158/79 = 2, => Number of moles of hydrogen = 2* 5 = 10.

Discussion

91.	What are the number of atoms of chlorine in 250.5 grams of Cl2O6?(a) 1.806 X 10^24(b) 2.408 X 10^24(c) 9.033 X 10^23(d) 6.022 X 10^23This question was addressed to me by my college director while I was bunking the class.This intriguing question comes from The Mole topic in division Moles, Density & Concentration of Basic Chemical Engineering
Answer» The CORRECT option is (a) 1.806 X 10^24 Best explanation: Number of MOLES of Cl2O6 = 250.5/167 = 1.5, => number of atoms of chlorine = 21.5(6.022 X 10^23) = 1.806 X 10^24.

Discussion

92.	Calculate the number of moles in 369 grams of CaOCl2?(a) 1(b) 2(c) 3(d) 4This question was addressed to me in quiz.I'm obligated to ask this question of The Mole in portion Moles, Density & Concentration of Basic Chemical Engineering
Answer» The CORRECT CHOICE is (C) 3 For explanation: Molecular weight of CaOCl2 = 127, => number of moles = 369/127 = 3.

Discussion

93.	How many grams of NaCl represent 1 mole?(a) 23(b) 35.5(c) 58.5(d) 69.5This question was addressed to me during an interview.This question is from The Mole in division Moles, Density & Concentration of Basic Chemical Engineering
Answer» The CORRECT option is (c) 58.5 For explanation: Molecular WEIGHT of NACL is 58.5 grams, => 1 mole REPRESENT 58.5 grams of NaCl.

Discussion

94.	How many atoms of carbon represent 1.5 mole?(a) 6.022 X 10^23(b) 1.2044 X 10^23(c) 3.011 X 10^23(d) 9.033 X 10^23I had been asked this question in exam.Enquiry is from The Mole in portion Moles, Density & Concentration of Basic Chemical Engineering
Answer» Correct answer is (d) 9.033 X 10^23 Explanation: Number of moles = number of atoms/Avogadro’s number, => 1.5 = N/6.022 X 10^23, => n = 9.033 X 10^23.

Discussion

95.	Calculate the number of moles in 42 grams of NaHCO3?(a) 0.5(b) 1(c) 1.5(d) 2I have been asked this question in a national level competition.This question is from The Mole in chapter Moles, Density & Concentration of Basic Chemical Engineering
Answer» CORRECT choice is (a) 0.5 For explanation: Molecular weight of NAHCO3 = 84 grams, => number of moles = 42/84 = 0.5.

Discussion

Explore topic-wise InterviewSolutions in .

What is the specific gravity of N2 at 27oC and 6 Pa with respect to 0.1 Kg/m^3?(a) 0.16(b) 0.33(c) 0.51(d) 0.89I have been asked this question in an online quiz.The query is from Specific Gravity in chapter Moles, Density & Concentration of Basic Chemical Engineering

What is the specific gravity of O2 at 27oC and 60 Pa with respect to 1 Kg/m^3?(a) 0.15(b) 0.28(c) 0.54(d) 0.76The question was asked in an internship interview.I would like to ask this question from Specific Gravity topic in division Moles, Density & Concentration of Basic Chemical Engineering

What is the specific gravity of 10 Kg of water occupied in 5 m3 with respect to 100 g/m^3?(a) 1(b) 5(c) 10(d) 20This question was addressed to me during an online interview.This question is from Specific Gravity topic in portion Moles, Density & Concentration of Basic Chemical Engineering

What is the specific gravity of 5 Kg of water occupied in 10 m3 with respect to 500 g/m^3?(a) 0.5(b) 1(c) 2(d) 5I got this question during an online exam.Enquiry is from Specific Gravity in division Moles, Density & Concentration of Basic Chemical Engineering

What is the specific gravity of 10 Kg of water occupied in 10 m3 with respect to 200 g/m^3?(a) 0.2(b) 0.5(c) 1(d) 5I have been asked this question during an interview.My question comes from Specific Gravity in division Moles, Density & Concentration of Basic Chemical Engineering

What is the API gravity of a substance with specific gravity 1?(a) 131.5(b) 141.5(c) 10(d) 50I have been asked this question in semester exam.My doubt is from Specific Gravity in portion Moles, Density & Concentration of Basic Chemical Engineering

API gravity is measured in,(a) Gravity meter scale(b) Hydrometer scale(c) Richer scale(d) None of the mentionedThe question was asked during an interview.Question is from Specific Gravity topic in division Moles, Density & Concentration of Basic Chemical Engineering

What is the unit of specific gravity?(a) Kg/m^3(b) N/m^3(c) m/s^2(d) DimensionlessI had been asked this question during an interview.My enquiry is from Specific Gravity topic in chapter Moles, Density & Concentration of Basic Chemical Engineering

What is the mass of a cube having surface area 24 m^2, and density 1 kg/m^3?(a) 1 kg(b) 2 kg(c) 4 kg(d) 8 kgThe question was posed to me in an internship interview.My question is taken from Density topic in division Moles, Density & Concentration of Basic Chemical Engineering

What is the mass of a liquid having density 20 kg/m^3, enclosed in a sphere of radius 1 m?(a) 80.7 kg(b) 83.7 kg(c) 85.7 kg(d) 88.7 kgI got this question in an online interview.My query is from Density in section Moles, Density & Concentration of Basic Chemical Engineering

Which of the following is not a unit of density?(a) Kg/m^3(b) N/m^3(c) N.s^2/m^4(d) g/cm^3This question was addressed to me in an online quiz.This interesting question is from Density topic in division Moles, Density & Concentration of Basic Chemical Engineering

What is the density of a substance of mass 10 grams and volume 5 liters?(a) 2 kg/m^3(b) 20 kg/m^3(c) 200 kg/m^3(d) 2000 kg/m^3The question was asked during an internship interview.I'm obligated to ask this question of Density in division Moles, Density & Concentration of Basic Chemical Engineering

What are the number of moles of hydrogen in NH4[Cr(SCN)4(NH3)2] if the weight of nitrogen in it is 49 grams?(a) 3.5(b) 5(c) 7(d) 10I got this question in a national level competition.Origin of the question is The Mole topic in section Moles, Density & Concentration of Basic Chemical Engineering

What are the number of moles of nitrogen in 274 grams of (NH4)2Ce(NO3)6?(a) 16(b) 8(c) 6(d) 4This question was addressed to me during an interview.This intriguing question originated from The Mole topic in portion Moles, Density & Concentration of Basic Chemical Engineering

What are the number of moles of Hydrogen in 158 grams of Ammonium Bicarbonate?(a) 5(b) 10(c) 15(d) 20I had been asked this question in examination.My question is from The Mole topic in chapter Moles, Density & Concentration of Basic Chemical Engineering

Calculate the number of moles in 369 grams of CaOCl2?(a) 1(b) 2(c) 3(d) 4This question was addressed to me in quiz.I'm obligated to ask this question of The Mole in portion Moles, Density & Concentration of Basic Chemical Engineering

How many grams of NaCl represent 1 mole?(a) 23(b) 35.5(c) 58.5(d) 69.5This question was addressed to me during an interview.This question is from The Mole in division Moles, Density & Concentration of Basic Chemical Engineering

How many atoms of carbon represent 1.5 mole?(a) 6.022 X 10^23(b) 1.2044 X 10^23(c) 3.011 X 10^23(d) 9.033 X 10^23I had been asked this question in exam.Enquiry is from The Mole in portion Moles, Density & Concentration of Basic Chemical Engineering

Calculate the number of moles in 42 grams of NaHCO3?(a) 0.5(b) 1(c) 1.5(d) 2I have been asked this question in a national level competition.This question is from The Mole in chapter Moles, Density & Concentration of Basic Chemical Engineering