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51.

________ flow rate of a process stream is the mass transported through a pipe per unit time.(a) Mass(b) Mole(c) Volume(d) None of the mentionedThis question was addressed to me in quiz.Enquiry is from Flow Rate in chapter Introductory Concepts of Chemical Process Calculation

Answer»

Right option is (a) MASS

The best I can EXPLAIN: Mass FLOW rate of a process stream is the mass TRANSPORTED through a pipe PER unit time.

52.

In barometer, the given space labelled as A, above the mercury is(a) Vacuum(b) Filled with Air(c) Filled with water(d) Filled with GasThe question was posed to me in semester exam.My enquiry is from Pressure and Hydrostatic Head-I in division Introductory Concepts of Chemical Process Calculation

Answer»

Right choice is (a) Vacuum

The explanation is: To correctly measure the ATMOSPHERIC PRESSURE, the space above the MERCURY level in a barometer is essentially vacuum. Otherwise, the fluid in the space will EXERT a pressure on the mercury surface.

53.

1 atm pressure is equal to(a) 101.3 kPa(b) 760 mm of Hg(c) 14.69 psi(d) All of the mentionedThis question was posed to me by my college professor while I was bunking the class.Origin of the question is Pressure and Hydrostatic Head-I in section Introductory Concepts of Chemical Process Calculation

Answer»

The CORRECT choice is (d) All of the mentioned

Explanation: 1 ATM = 101.3 kPa = 760 mm of Hg = 14.69 PSI.

54.

Find the correct statement for ppm(a) For solids and liquids, it is mole ratio(b) For gases, it is mole ratio(c) It is mole ration for every phase of matter(d) It is mass ratio for every phase of matterI have been asked this question in a job interview.My doubt is from Concentration-I topic in division Introductory Concepts of Chemical Process Calculation

Answer»

The CORRECT option is (B) For gases, it is mole RATIO

For EXPLANATION: For gases, it is mole ratio and for LIQUIDS and solids, it is mass ratio.

55.

A material have a mass of 2 gms and volume of 4 cm3. The material would _____ on water surface.(a) Completely Float(b) Completely Sink(c) Partially Sink(d) None of the mentionedThis question was posed to me in my homework.The question is from Density and specific gravity-III in portion Introductory Concepts of Chemical Process Calculation

Answer»

Correct answer is (B) Completely Sink

For explanation: Specific GRAVITY of the MATERIAL is LESS than one.

56.

A substance has a mass of 20 kg and volume of 40 m3. The specific gravity of the substance is 0.80 kg/cm3. What is the reference density (Kg/m3)?(a) 0.25(b) 0.50(c) 0.75(d) 1.00This question was posed to me in my homework.Origin of the question is Density and specific gravity-III in chapter Introductory Concepts of Chemical Process Calculation

Answer» CORRECT choice is (a) 0.25

The explanation: Specific GRAVITY = DENSITY of the substance / Reference density.
57.

The density of material is 5 kg/cm3. What is its specific volume cm3/kg?(a) 0.2(b) 0.5(c) 5.0(d) 1.0This question was addressed to me in an interview for job.The origin of the question is Density and specific gravity-II in portion Introductory Concepts of Chemical Process Calculation

Answer»

The correct CHOICE is (a) 0.2

Best EXPLANATION: Inverse of DENSITY is specific volume.

58.

What is mole percentage of C2H4?(a) 0.2(b) 0.4(c) 0.6(d) 0.8The question was asked in an interview for job.I want to ask this question from Mole and Molecular Weight topic in section Introductory Concepts of Chemical Process Calculation

Answer»

Right choice is (B) 0.4

Easiest EXPLANATION: Mole percentage = Moles of the component / TOTAL moles.

59.

One mole of H2O equals(a) 22.4 litre at 1 atm and 250C(b) 6.02 x 10^23 atoms of hydrogen and 6.02 x 10^23 atoms of oxygen(c) 18 g(d) 1 galI got this question in an online quiz.My enquiry is from Mole and Molecular Weight-V topic in portion Introductory Concepts of Chemical Process Calculation

Answer»

The CORRECT OPTION is (C) 18 g

The explanation: One mole of H2O = 18 gms.

60.

How many gms of NaOH is there in 0.002 lb mole NaOH?(a) 32.36(b) 36.32(c) 24.28(d) 28.24I had been asked this question in a national level competition.I'd like to ask this question from Mole and Molecular Weight-V in section Introductory Concepts of Chemical Process Calculation

Answer»

The CORRECT answer is (b) 36.32

To elaborate: 1 lb mole of NaOH = 40 lb of NaOH = 40*454 GMS of NaOH.

61.

What is the molarity of a solution made by diluting 500 mL of a 2.50 M solution to a final volume of 800 mL?(a) 0.5265 M(b) 1.5625 M(c) 2.5689 M(d) 3.4586 MThe question was posed to me in an online interview.I'd like to ask this question from Concentration-II in portion Introductory Concepts of Chemical Process Calculation

Answer»

Correct answer is (B) 1.5625 M

To ELABORATE: MOLARITY = Moles / VOLUME.

62.

What is the total hardness of water in mg/L if the concentration of Ca and Mg are 56.7 mg/L and 9.8 mg/L?(a) 182.1(b) 66.5(c) 133(d) 91.05I have been asked this question by my school principal while I was bunking the class.I would like to ask this question from Concentration-I in division Introductory Concepts of Chemical Process Calculation

Answer» RIGHT CHOICE is (a) 182.1

To ELABORATE: g CACO3 /g CA= 2.5 and g CaCO3 /g Mg = 4.118

Hardness of water = 2.5(56.7) + 4.118(9.8).
63.

Concentration of the material in kg/L in the exit stream(a) 0.3864(b) 0.2033(c) 4.0673(d) 0.7728I got this question in an internship interview.The question is from Density and specific gravity-II in division Introductory Concepts of Chemical Process Calculation

Answer» CORRECT ANSWER is (a) 0.3864

The explanation is: Take 1 MIN. basis and then USING the flow rate of liquid, density of liquid and percentage of MATERIAL calculate the concentration.
64.

How many moles of H2O are there in the bucket?(a) 1(b) 2(c) 4(d) 6The question was asked during an online interview.The query is from Mole and Molecular Weight topic in division Introductory Concepts of Chemical Process Calculation

Answer»

Right OPTION is (B) 2

The explanation is: Number of moles = MASS / molecular WEIGHT.

65.

What is the formula for a solid compound that contains 42.11% C, 51.46% O, and 6.43% H and having molecular weight about 341.(a) C10 O12H29(b) C11O13 H(c) C12O11H22(d) C12O10H37This question was addressed to me in semester exam.This interesting question is from Mole and Molecular Weight-III topic in chapter Introductory Concepts of Chemical Process Calculation

Answer»

The correct option is (C) C12O11H22

Easiest EXPLANATION: TAKE 100 g of the compound and calculate the ratio of the molecules, then MAKE it integer to get the chemical formula.

66.

Moles of a substance transported through a pipe per unit time is called(a) Molar flow rate(b) Molar volume(c) Molar mass(d) None of the mentionedThe question was posed to me in quiz.My enquiry is from Flow Rate in division Introductory Concepts of Chemical Process Calculation

Answer»

The CORRECT choice is (a) MOLAR flow rate

The explanation: Moles of a substance transported through a pipe per UNIT time is CALLED molar flow rate.

67.

What is the mass flow rate of a material, if 20 ml of it is collected in 20 sec. The density of the material is 0.5 gm/ml.(a) 0.1(b) 0.5(c) 1.0(d) 1.5This question was posed to me in class test.This question is from Flow Rate in section Introductory Concepts of Chemical Process Calculation

Answer» RIGHT answer is (B) 0.5

Easy EXPLANATION: Mass FLOW RATE =Mass/time.
68.

1 atm pressure equals to(a) 29.92 in Hg(b) 25.65 in Hg(c) 27.68 in Hg(d) 24.74 in HgI got this question by my college director while I was bunking the class.My question comes from Pressure and Hydrostatic Head-III topic in chapter Introductory Concepts of Chemical Process Calculation

Answer» RIGHT ANSWER is (a) 29.92 in Hg

To ELABORATE: 1 ATM = 29.92 in Hg.
69.

Which one is the most concentrated solution?(a) 20 g of NaOH in 100 mL of water(b) 150 g of NaOH in 200 mL of water(c) 180 g of NaOH in 300 mL of water(d) 250 g of NaOH in 600 mL of waterI got this question during an interview.The origin of the question is Concentration-II in portion Introductory Concepts of Chemical Process Calculation

Answer»

The correct ANSWER is (b) 150 G of NAOH in 200 ML of water

Explanation: Concentration = Mass / Volume.

70.

How many moles of Ar are there in the cylinder?(a) 1(b) 2(c) 4(d) 6This question was addressed to me in homework.This is a very interesting question from Mole and Molecular Weight in chapter Introductory Concepts of Chemical Process Calculation

Answer»

Right option is (a) 1

For explanation: NUMBER of moles = mass / MOLECULAR WEIGHT.

71.

A cube of ice is floating on water surface and when it completely melts, the level of water would _______(a) Increase(b) Decrease(c) Remains unchanged(d) None of the mentionedThis question was addressed to me at a job interview.This intriguing question comes from Density and specific gravity-III in section Introductory Concepts of Chemical Process Calculation

Answer»

The correct option is (c) Remains unchanged

The best I can EXPLAIN: There is no CHANGE in the volume of the water as the SPACE occupied by the ICE inside the water body is FILLED with it.

72.

Specific gravity of a substance is 2.42. What is the density of the substance in lb/ft^3?(a) 151(b) 252(c) 302(d) 402I have been asked this question during an online interview.Enquiry is from Density and specific gravity-I topic in section Introductory Concepts of Chemical Process Calculation

Answer» RIGHT option is (a) 151

The explanation is: SPECIFIC GRAVITY is the RATIO of the density of a SUBSTANCE to the density of a reference material.
73.

What is the mass fraction ofNa atom in NaOH molecule?(a) 0.33(b) 0.66(c) 0.575(d) 1.150This question was addressed to me in quiz.The question is from Choosing a Basis topic in section Introductory Concepts of Chemical Process Calculation

Answer»

The CORRECT OPTION is (a) 0.33

Best explanation: Take basis: 1 KG MOLE of NaOH.

74.

If in a compound the moles of consisting atoms are doubled then the mole fraction of a particular atom will be(a) Double(b) Half(c) Remain same(d) None of the mentionedI got this question in class test.Question is taken from Mole and Molecular Weight-III in section Introductory Concepts of Chemical Process Calculation

Answer» CORRECT ANSWER is (a) Double

Explanation: MOLE fraction of X = moles of the X/total moles.
75.

What is the mole fraction of O2?(a) 0.2(b) 0.4(c) 0.6(d) 0.8This question was posed to me in an interview for internship.This is a very interesting question from Mole and Molecular Weight topic in section Introductory Concepts of Chemical Process Calculation

Answer»

The CORRECT answer is (b) 0.4

Explanation: MOLE FRACTION = Moles of the component / TOTAL moles.

76.

What is the percent water in CuSO4.5H2O?(a) 12(b) 14(c) 16(d) 18I got this question in an interview for job.This intriguing question originated from Mole and Molecular Weight-III in portion Introductory Concepts of Chemical Process Calculation

Answer»

Correct OPTION is (c) 16

Explanation: PERCENTAGE water = mass of water in the MOLECULE/Total mass of the molecule.

77.

Volumetric flow rate of a process stream is the ________ transported through the pipe per unit time.(a) Mass(b) Mole(c) Volume(d) None of the mentionedI got this question during an interview for a job.I want to ask this question from Flow Rate topic in section Introductory Concepts of Chemical Process Calculation

Answer» RIGHT option is (c) Volume

The explanation is: Volumetric flow rate of a process stream is the volume TRANSPORTED through the pipe per UNIT time.
78.

Piezometer is used for the pressure measurement of only _______(a) Solid(b) Liquid(c) Gas(d) None of the mentionedThe question was posed to me during an interview.Question is taken from Pressure and Hydrostatic Head-III topic in chapter Introductory Concepts of Chemical Process Calculation

Answer»
79.

Given that both liquid A and liquid B exert the same amount of pressure, what would be the height of column of liquid A if the density of liquid A is twice the density of liquid B and the height of column of liquid B is 10 cm?(a) 5 cm(b) 10 cm(c) 20 cm(d) None of the aboveThe question was asked at a job interview.My question is based upon Pressure and Hydrostatic Head-III topic in division Introductory Concepts of Chemical Process Calculation

Answer» CORRECT CHOICE is (a) 5 cm

Explanation: DGH = CONSTANT.
80.

For the given manometer(a) P1 + ρ1d2g = P2 + ρ2d2g(b) P1 + ρ1d1g = P2 + ρ2d2g(c) P1 + ρ1d1g = P2 + ρ2d2g + ρ3d3g(d) None of the mentionedI got this question in an interview for internship.The above asked question is from Pressure and Hydrostatic Head-I in portion Introductory Concepts of Chemical Process Calculation

Answer»

The correct option is (C) P1 + ρ1d1g = P2 + ρ2d2g + ρ3d3g

To explain I would say: P1 + ρ1d2g = P2 + ρ2d2g + ρ3d3g. For same liquid at same LEVEL, PRESSURE will be ALWAYS same.

81.

What is mole percentage of H2O?(a) 0.2(b) 0.4(c) 0.6(d) 0.8This question was addressed to me in a job interview.The above asked question is from Mole and Molecular Weight in chapter Introductory Concepts of Chemical Process Calculation

Answer»

The CORRECT choice is (B) 0.4

Best EXPLANATION: Mole PERCENTAGE = MOLES of the component / Total moles.

82.

How many moles of Hydrogen are there in the bucket?(a) 11.00(b) 11.16(c) 11.56(d) 11.98The question was asked in a job interview.My question is taken from Mole and Molecular Weight-IV topic in section Introductory Concepts of Chemical Process Calculation

Answer»

Right option is (b) 11.16

For explanation I WOULD SAY: Moles of H = Moles of NAOH + 2(Moles of H2O) + 2(Moles of H2SO4).

83.

How many moles of Hydrogen are there in 1 mole of (NH4)2HPO4?(a) 1(b) 4(c) 5(d) 9I had been asked this question by my college director while I was bunking the class.The question is from Mole and Molecular Weight-V topic in division Introductory Concepts of Chemical Process Calculation

Answer»

The CORRECT answer is (d) 9

Explanation: There are NINE HYDROGEN atoms in a SINGLE molecule.

84.

Mass flow rate of the liquid flowing through a pipe, 100 grams of the liquid was collected in 10 seconds?(a) 0.01 kg/s(b) 0.05 kg/s(c) 0.1 kg/s(d) 0.5 kg/sThis question was posed to me during an online exam.Origin of the question is Flow Rate topic in chapter Introductory Concepts of Chemical Process Calculation

Answer»

The correct ANSWER is (a) 0.01 kg/s

The best I can EXPLAIN: MASS FLOW rate = 0.1/ 10 = 0.01 kg/s.

85.

Find out the correct statement: 200˚C is equal to(a) 273 K(b) 292 ˚F(c) 852 ˚R(d) None of the mentionedThis question was posed to me in an interview for internship.I'm obligated to ask this question of Temperature topic in section Introductory Concepts of Chemical Process Calculation

Answer» CORRECT ANSWER is (C) 852 ˚R

For EXPLANATION: ∆˚F = ∆˚R, ∆˚C = ∆˚K, ∆˚C = 1.8 ∆˚F and ∆˚K = 1.8∆˚F.
86.

How many gms of NaCl are required to prepare 2.5 L of 0.6 M solution?(a) 22(b) 44(c) 66(d) 88This question was posed to me in unit test.The above asked question is from Concentration-II topic in section Introductory Concepts of Chemical Process Calculation

Answer»

The CORRECT CHOICE is (d) 88

Explanation: MOLARITY = MOLES / VOLUME.

87.

What is the ppm concentration of 6.00 mL sample of solution that has 3.6 x 10-4 g of sodium ions?(a) 20(b) 40(c) 60(d) 80I have been asked this question in unit test.I want to ask this question from Concentration-I topic in division Introductory Concepts of Chemical Process Calculation

Answer»

The CORRECT choice is (C) 60

To EXPLAIN: CONCENTRATION PARTS per million.

88.

What is weight percentage of N2?(a) 22.58(b) 25.86(c) 42.56(d) 54.87The question was asked by my school principal while I was bunking the class.This key question is from Mole and Molecular Weight topic in section Introductory Concepts of Chemical Process Calculation

Answer» CORRECT choice is (a) 22.58

To explain I would say: WEIGHT PERCENTAGE = MASS of the component / TOTAL mass.
89.

What is mole percentage of NaOH?(a) 20.4(b) 19.4(c) 18.4(d) 17.4I had been asked this question in my homework.Query is from Mole and Molecular Weight-IV in section Introductory Concepts of Chemical Process Calculation

Answer»

The correct option is (b) 19.4

To EXPLAIN I WOULD SAY: Mole percentage = Moles of the component / Total moles.

90.

A bucket contains 10 kg of water and 10 kg of NaOH. The respective mass fraction of water and the mole fraction of NaOH are(a) 0.5 and 0.31(b) 1.0 and 0.62(c) 0.5 and 0.69(d) 1.0 and 0.50I have been asked this question in examination.Asked question is from Mole and Molecular Weight-III topic in portion Introductory Concepts of Chemical Process Calculation

Answer»

Right OPTION is (a) 0.5 and 0.31

The EXPLANATION is: MOLE FRACTION of X = moles of X/total moles and mass fraction of X = mass of X/total mass.

91.

Pressure measured above atmospheric pressure is called(a) Absolute pressure(b) Gauge pressure(c) Static pressure(d) None of the mentionedI have been asked this question in a job interview.My enquiry is from Pressure and Hydrostatic Head-II in division Introductory Concepts of Chemical Process Calculation

Answer»

Right OPTION is (b) GAUGE pressure

The BEST I can EXPLAIN: Pressure measured above atmospheric pressure is called ABSOLUTE pressure.

92.

In the sketch, the height h is equivalent to 150 kPa and the barometer reading is 100 kPa. What is pressure inside the tank that is attached to the manometer?(a) 250 kPa(b) 150 kPa(c) 100 kPa(d) 50 kPaI had been asked this question in an online interview.Question is taken from Pressure and Hydrostatic Head-II topic in division Introductory Concepts of Chemical Process Calculation

Answer»

Right choice is (a) 250 kPa

For EXPLANATION I WOULD SAY: Pressure inside the tank = atmospheric pressure + pressure DUE to liquid HEIGHT h.

93.

Specific gravity = 0.80 26˚/4˚ notation represents(a) Specific gravity when the solution is at 26˚C and the reference substance is at 4˚C is 0.80(b) Specific gravity when the solution is at 4˚C and the reference substance is at 26˚C is 0.80(c) Both a and b(d) Neither a nor bThe question was posed to me in an interview for internship.Question is from Density and specific gravity-I in portion Introductory Concepts of Chemical Process Calculation

Answer»

Right choice is (a) SPECIFIC gravity when the solution is at 26˚C and the reference substance is at 4˚C is 0.80

To explain: SIMPLE RULE for the REPRESENTATION.

94.

Density of water is(a) 1 gm/cm^3(b) 1000 Kg/m^3(c) 62.43 lb/ft^3(d) All of the mentionedThis question was addressed to me in an internship interview.The above asked question is from Density and specific gravity-I in division Introductory Concepts of Chemical Process Calculation

Answer»

The CORRECT OPTION is (a) 1 gm/cm^3

Explanation: DENSITY of WATER = 1 gm/cm^3 = 1000 Kg/m^3 = 62.43 lb/ft^3.

95.

Specific volume is the inverse of(a) Volume(b) Pressure(c) Density(d) Flow rateI had been asked this question in an interview for job.I need to ask this question from Density and specific gravity-I in division Introductory Concepts of Chemical Process Calculation

Answer»

Correct ANSWER is (C) Density

Explanation: Specific VOLUME is the inverse of density.

96.

Mass per unit volume is called(a) Density(b) Molecular weight(c) Molar mass(d) Mole fractionThis question was addressed to me in an interview for job.Origin of the question is Density and specific gravity-I in chapter Introductory Concepts of Chemical Process Calculation

Answer»

The correct option is (a) DENSITY

The explanation is: MASS per unit VOLUME is called density.

97.

A high energy producing gas contains the following mixtures of gases, 20% H2O, 40% CH4 and 40% CO2. The average molecular weight of the gas is?(a) 25.6(b) 26.6(c) 27.6(d) 28.6The question was asked in exam.The doubt is from Choosing a Basis topic in division Introductory Concepts of Chemical Process Calculation

Answer»

Right choice is (c) 27.6

The explanation: Take a BASIS 100 KG mole and calculate the total weight of the gas for 100 kg mole. Next step, dividing it by 100 kg mole get the MOLECULAR weight of the gas.

98.

How many moles of C3H8 are there in the bucket?(a) 1(b) 2(c) 4(d) 6I got this question in an international level competition.This interesting question is from Mole and Molecular Weight in section Introductory Concepts of Chemical Process Calculation

Answer»

The CORRECT CHOICE is (a) 1

To explain: NUMBER of moles = mass / molecular WEIGHT.

99.

What is the mole fraction of He?(a) 0.2(b) 0.4(c) 0.6(d) 0.8This question was posed to me in final exam.I'd like to ask this question from Mole and Molecular Weight topic in division Introductory Concepts of Chemical Process Calculation

Answer» CORRECT choice is (b) 0.4

To explain I WOULD say: Mole FRACTION = MOLES of the component / Total moles.
100.

The smallest particle of a substance that is capable of independent existence is _________(a) Atom(b) Molecule(c) Electron(d) ProtonI had been asked this question by my college professor while I was bunking the class.Question is taken from Mole and Molecular Weight-V in portion Introductory Concepts of Chemical Process Calculation

Answer» CORRECT option is (b) Molecule

For explanation: The SMALLEST PARTICLE of a SUBSTANCE that is capable of independent existence is molecule.