Multiple choice question for engineering
Set 1
1-10. A bucket contains 48 gms of NaOH, 56 gms of H2O and 184 gms of H2SO4. (Molecular weights of the components are 40, 18 and 98 respectively)
1. How many moles of NaOH are there in the bucket?
a) 1.0
b) 1.2
c) 1.4
d) 1.6
Answer
Answer: b [Reason:] Number of moles = mass / molecular weight.
2. How many moles of H2SO4 are there in the bucket?
a) 1.44
b) 1.88
c) 2.44
d) 2.88
Answer
Answer: b [Reason:] Number of moles = mass / molecular weight.
3. How many moles of H2O are there in the bucket?
a) 3.1
b) 3.2
c) 3.3
d) 3.4
Answer
Answer: a [Reason:] Number of moles = mass / molecular weight.
4. What are the number moles of Oxygen present there in the bucket?
a) 14.82
b) 13.82
c) 12.82
d) 11.82
Answer
Answer: d [Reason:] Moles of Oxygen = Moles of NaOH + Moles of H2O + 4(Moles of H2SO4).
5. How many moles of Hydrogen are there in the bucket?
a) 11.00
b) 11.16
c) 11.56
d) 11.98
Answer
Answer: b [Reason:] Moles of H = Moles of NaOH + 2(Moles of H2O) + 2(Moles of H2SO4).
6. What is the weight percentage of H2O?
a) 19.44
b) 14.42
c) 12.56
d) 10.28
Answer
Answer: a [Reason:] Weight percentage = mass of the component / Total mass.
7. What is mole percentage of H2SO4?
a) 10.4
b) 20.4
c) 30.4
d) 40.4
Answer
Answer: c [Reason:] Mole percentage = Moles of the component / Total moles.
8. What is the weight percentage of NaOH?
a) 14.67
b) 15.67
c) 16.67
d) 17.67
Answer
Answer: c [Reason:] Weight percentage = mass of the component / Total mass.
9. What is mole percentage of NaOH?
a) 20.4
b) 19.4
c) 18.4
d) 17.4
Answer
Answer: b [Reason:] Mole percentage = Moles of the component / Total moles.
10. What is the weight percentage of H2SO4 ?
a) 14.82
b) 25.69
c) 58.67
d) 63.88
Answer
Answer: d [Reason:] Weight percentage = mass of the component / Total mass.
Set 2
1-10. A bucket contains 48 gms of NaOH, 56 gms of H2O and 184 gms of H2SO4. (Molecular weights of the components are 40, 18 and 98 respectively)
1. How many moles of NaOH are there in the bucket?
a) 1.0
b) 1.2
c) 1.4
d) 1.6
Answer
Answer: b [Reason:] Number of moles = mass / molecular weight.
2. How many moles of H2SO4 are there in the bucket?
a) 1.44
b) 1.88
c) 2.44
d) 2.88
Answer
Answer: b [Reason:] Number of moles = mass / molecular weight.
3. How many moles of H2O are there in the bucket?
a) 3.1
b) 3.2
c) 3.3
d) 3.4
Answer
Answer: a [Reason:] Number of moles = mass / molecular weight.
4. What are the number moles of Oxygen present there in the bucket?
a) 14.82
b) 13.82
c) 12.82
d) 11.82
Answer
Answer: d [Reason:] Moles of Oxygen = Moles of NaOH + Moles of H2O + 4(Moles of H2SO4).
5. How many moles of Hydrogen are there in the bucket?
a) 11.00
b) 11.16
c) 11.56
d) 11.98
Answer
Answer: b [Reason:] Moles of H = Moles of NaOH + 2(Moles of H2O) + 2(Moles of H2SO4).
6. What is the weight percentage of H2O?
a) 19.44
b) 14.42
c) 12.56
d) 10.28
Answer
Answer: a [Reason:] Weight percentage = mass of the component / Total mass.
7. What is mole percentage of H2SO4?
a) 10.4
b) 20.4
c) 30.4
d) 40.4
Answer
Answer: c [Reason:] Mole percentage = Moles of the component / Total moles.
8. What is the weight percentage of NaOH?
a) 14.67
b) 15.67
c) 16.67
d) 17.67
Answer
Answer: c [Reason:] Weight percentage = mass of the component / Total mass.
9. What is mole percentage of NaOH?
a) 20.4
b) 19.4
c) 18.4
d) 17.4
Answer
Answer: b [Reason:] Mole percentage = Moles of the component / Total moles.
10. What is the weight percentage of H2SO4 ?
a) 14.82
b) 25.69
c) 58.67
d) 63.88
Answer
Answer: d [Reason:] Weight percentage = mass of the component / Total mass.
Set 3
1. What is the percent by weight of C in CO2?
Molecular weight of C and Oxygen are 12 and 16 respectively?
a) 25
b) 50
c) 75
d) None of the mentioned
Answer
Answer: b [Reason:] Percentage by weight = mass of the component / Total mass.
2. How many moles of Hydrogen are there in 1 mole of (NH4)2HPO4?
a) 1
b) 4
c) 5
d) 9
Answer
Answer: 9 [Reason:] There are nine Hydrogen atoms in a single molecule.
3. Relative molecular masses can be calculated
a) By the relative atomic mass
b) By the relative mass of a covalent compound
c) if individual relative atomic masses are added
d) By adding relative compound masses
Answer
Answer: c [Reason:] Relative molecular masses can be calculated if individual relative atomic masses are added.
4. What is the percentage by weight of Nitrogen in NH3?
a) 82.35
b) 83.40
c) 88.12
d) 94.56
Answer
Answer: a [Reason:] Percentage by weight = mass of the component / Total mass.
5. Relative molecular mass of CO2 is _________
a) 22
b) 44
c) 66
d) 88
Answer
Answer: b [Reason:] Relative molecular mass = Molecular mass of C + 2(Molecular mass of Oxygen).
6. How many gms of NaOH is there in 0.002 lb mole NaOH?
a) 32.36
b) 36.32
c) 24.28
d) 28.24
Answer
Answer: b [Reason:] 1 lb mole of NaOH = 40 lb of NaOH = 40*454 gms of NaOH.
7. The quantity of matter present in an object is
a) Mass
b) Molecular weight
c) Mole
c) Molar mass
Answer
Answer:a [Reason:] The quantity of matter present in an object is mass.
8. The smallest particle of a substance that is capable of independent existence is _________
a) Atom
b) Molecule
c) Electron
d) Proton
Answer
Answer: b [Reason:] The smallest particle of a substance that is capable of independent existence is molecule.
9. One mole of H2O equals
a) 22.4 litre at 1 atm and 250C
b) 6.02 x 1023 atoms of hydrogen and 6.02 x 1023 atoms of oxygen
c) 18 g
d) 1 gal
Answer
Answer:c [Reason:] One mole of H2O = 18 gms.
10. What is the percent by weight of P in the compound in P4S3?
a) 28.3
b) 56.4
c) 25.3
d) 58.3
Answer
Answer: b [Reason:] Percentage by weight = mass of the component / Total mass.
Set 4
1. What is the percent by weight of C in CO2?
Molecular weight of C and Oxygen are 12 and 16 respectively?
a) 25
b) 50
c) 75
d) None of the mentioned
Answer
Answer: b [Reason:] Percentage by weight = mass of the component / Total mass.
2. How many moles of Hydrogen are there in 1 mole of (NH4)2HPO4?
a) 1
b) 4
c) 5
d) 9
Answer
Answer: 9 [Reason:] There are nine Hydrogen atoms in a single molecule.
3. Relative molecular masses can be calculated
a) By the relative atomic mass
b) By the relative mass of a covalent compound
c) if individual relative atomic masses are added
d) By adding relative compound masses
Answer
Answer: c [Reason:] Relative molecular masses can be calculated if individual relative atomic masses are added.
4. What is the percentage by weight of Nitrogen in NH3?
a) 82.35
b) 83.40
c) 88.12
d) 94.56
Answer
Answer: a [Reason:] Percentage by weight = mass of the component / Total mass.
5. Relative molecular mass of CO2 is _________
a) 22
b) 44
c) 66
d) 88
Answer
Answer: b [Reason:] Relative molecular mass = Molecular mass of C + 2(Molecular mass of Oxygen).
6. How many gms of NaOH is there in 0.002 lb mole NaOH?
a) 32.36
b) 36.32
c) 24.28
d) 28.24
Answer
Answer: b [Reason:] 1 lb mole of NaOH = 40 lb of NaOH = 40*454 gms of NaOH.
7. The quantity of matter present in an object is
a) Mass
b) Molecular weight
c) Mole
c) Molar mass
Answer
Answer:a [Reason:] The quantity of matter present in an object is mass.
8. The smallest particle of a substance that is capable of independent existence is _________
a) Atom
b) Molecule
c) Electron
d) Proton
Answer
Answer: b [Reason:] The smallest particle of a substance that is capable of independent existence is molecule.
9. One mole of H2O equals
a) 22.4 litre at 1 atm and 250C
b) 6.02 x 1023 atoms of hydrogen and 6.02 x 1023 atoms of oxygen
c) 18 g
d) 1 gal
Answer
Answer:c [Reason:] One mole of H2O = 18 gms.
10. What is the percent by weight of P in the compound in P4S3?
a) 28.3
b) 56.4
c) 25.3
d) 58.3
Answer
Answer: b [Reason:] Percentage by weight = mass of the component / Total mass.
Set 5
1-10. A cylinder contains 56 gms of N2, 128 gms of O2 and 64 gms of SO2. (Molecular weights of the components are 28, 64 and 64 respectively)
1. How many moles of N2 are there in the cylinder?
a) 1
b) 2
c) 4
d) 6
Answer
Answer: b [Reason:] Number of moles = mass / molecular weight.
2. How many moles of O2 are there in the cylinder?
a) 1
b) 2
c) 4
d) 6
Answer
Answer: b [Reason:] Number of moles = mass / molecular weight.
3. How many moles of SO2 are there in the cylinder?
a) 1
b) 2
c) 4
d) 6
Answer
Answer: a [Reason:] Number of moles = mass / molecular weight.
4. What are the number moles of Oxgen present there in the cylinder?
a) 1
b) 2
c) 3
d) 4
Answer
Answer: c [Reason:] Number of moles of O2 = 2+1 = 3.
5. How many moles of Sulfur are there in the cylinder?
a) 1
b) 2
c) 4
d) 6
Answer
Answer: a [Reason:] Number of moles of Sulfur = No. of moles of SO2.
6. What is the mole fraction of N2?
a) 0.2
b) 0.4
c) 0.6
d) 0.8
Answer
Answer: b [Reason:] Mole fraction = Moles of the component / Total moles.
7. What is the mole fraction of O2?
a) 0.2
b) 0.4
c) 0.6
d) 0.8
Answer
Answer: b [Reason:] Mole fraction = Moles of the component / Total moles.
8. What is the mole fraction of SO2?
a) 0.2
b) 0.4
c) 0.6
d) 0.8
Answer
Answer: a [Reason:] Mole fraction = Moles of the component / Total moles.
9. What is weight percentage of N2?
a) 22.58
b) 25.86
c) 42.56
d) 54.87
Answer
Answer: a [Reason:] Weight percentage = mass of the component / Total mass.
10. What is weight percentage of O2?
a) 51.61
b) 61.71
c) 71.81
d) 81.91
Answer
Answer: a [Reason:] Weight percentage = mass of the component / Total mass.
