Multiple choice question for engineering
1. In engineering drawing, which type of line indicates that there is a change of plane?
a) Continuous thin wavy
b) Long chain thin
c) Continuous thick
d) Medium thick short dashes
Answer: c [Reason:] In engineering drawing, a change of plane is indicated by drawing continuous thick lines. Continuous thin lines are used for indicating dimension line, hatching line, revolved section, etc. Long chain lines are used to indicate center line, cutting lines.
2. Which of the following lines are used to show that the object is cut and then viewed?
a) Hidden lines
b) Leader lines
c) Centre lines
d) Hatching Lines
Answer: d [Reason:] Hatching lines are used to show that the orthographic view is drawn after a section of the object is cut. They indicate that the object is cut and it shows the remaining solid body. Hidden lines are used to indicate holes or slots.
3. What do hidden lines in orthographic projections denote?
a) Holes or slots
b) Change of Plane
c) Position of cut
d) Centre of a circle or cylinder
Answer: a [Reason:] Hidden lines denote those parts which cannot be seen when viewing the object. They are used when there are holes or slots in the object, if they cannot be viewed directly. Change of plane is indicated by outlines. Position of cut is denoted by section line.
4. From the fbelow figure, what is the name of the line X?
b) Section line
c) Hidden line
Answer: c [Reason:] Hidden lines are dashed lines with dashes equaling 2mm and the gap 1mm. These lines depict that there is a hole or slot i.e. no solid part is present there. Section line are long chain thin lines with thick ends.
5. What is the type of line used for line a?
a) Continuous thick
b) Continuous thin straight
c) Medium thick short dashes
d) Continuous thin wavy
Answer: b [Reason:] Continuous thin straight lines are used to denote the dimensions of the object. Thin lines are used so as to distinguish between outline and the dimension line. Continuous thin wavy lines are used to indicate short breaks or irregular boundary line.
6. The axis of the cylinder or sphere is denoted by which of the following line?
a) Section line
b) Centre line
c) Hidden line
d) Leader line
Answer: b [Reason:] Centre line shows the axis of the cylinder or sphere. These lines generally pass through the centre of the circle. For a cylinder, they generally are parallel to the height of the cylinder. For circles, two centre lines are drawn perpendicular to each other passing through the centre of the circle.
7. What is the standard length and width of the arrowhead of dimension lines?
a) 2mm and 2mm
b) 3mm and 1mm
c) 4mm and 2mm
d) 3mm and 2mm
Answer: b [Reason:] Arrowheads of dimension lines have a length of 3mm and 1mm wide. When drawing the arrowheads the ratio, length: width is to be maintained at 3:1. The arrowheads can be drawn with length 6mm and breadth 2mm, since the ratio is the same.
8. What is the length of the short dashes of the centre lines?
Answer: b [Reason:] Centre line consists of long dash of 8-10mm, a gap of 1mm, short dash of 2mm and then a gap of 1mm. This pattern continues throughout the centre line. In case of section line, the ends of the section line are thickened. This is how section line and centre line are different.
9. Among the following, which of the representation is wrong?
Answer: b [Reason:] For proper dimensioning, it is important for the lines to meet. One line cannot be in air with respect to the other intersecting line; they should meet at some point. If the lines do not meet, dimensions will not have accuracy.
10. Which type of line is used to join the dimension line and the curve that needs to be dimensioned?
a) Leader line
c) Dimension line
d) Section line
Answer: a [Reason:] Leader lines lead the dimension line to the curve that needs to be dimensioned. It is a bridge connecting two lines. Outlines are the main or most prominent lines of the object when viewed for drawing. Dimension lines are used to denote the particular dimensions.
11. What is the difference between the section line and the centre line?
a) The length of the long dashes
b) The length of short dashes
c) The width of the gap
d) The two ends of the lines
Answer: d [Reason:] The ends of a section line are thickened so as to distinguish it from the centre line. The rest of the section line has the same thickness and dimensions as that of the centre line. The thickening of the ends in the section line is also used to denote the direction of viewing.
1. In electrolytic conductors, the conductance is due to_____________
a) Flow of free mobile electrons
b) Movement of ions
c) Either movement of electrons or ions
d) Cannot be said
Answer: b [Reason:] In metallic conductors, the conductance is due to the flow of free mobile electrons and in electrolytic conductors, the conductance is due to the movement of ions in a solution of fused electrolyte.
2. Which of the following is the example of the electrolytes?
Answer: a [Reason:] The acids and bases are the examples of the electrolytes and some solid salts, metals, alloys and oxides are the examples of the metallic conductors.
3. The resistance of the conductor in the electrolytic cell ___________with increase in temperature.
c) Slightly increase
d) Do no change
Answer: b [Reason:] The resistance of the conduction in the electrolytic cell decreases with increase in the temperature. In metallic conductors, resistance of the conductor increases with increase in temperature.
4. The process of decomposition of an electrolyte by passing electric current through its solution is called as__________
d) Electrochemical cell
Answer: c [Reason:] The process of decomposition of an electrolyte by passing electric current through its solution is called as electrolysis.
5. Specific conductance is expressed in terms of__________
c) Ohm-1 cm-1
d) Ohm-1 cm
Answer: c [Reason:] Specific conductance is expressed in terms of ohm-1 cm-1 As we know that k=l/S * 1/S = cm/[(cm)2 * ohm] =Ohm-1 cm-1.
6. The specific conductance of the electrolyte ___________on dilution.
c) Slightly increases
d) Cannot be determined
Answer: b [Reason:] The specific conductance of the electrolyte decreases on dilution. Equivalent conductance increases on dilution.
7. Which of the following are the strong electrolytes?
b) Acetic acid
c) Propinoic acid
Answer: a [Reason:] The strong electrolyte is HCL because it is strong acid and acts as electrolyte. The acetic acid, propinoic acid and H2SO3 are weak acid electrolytes.
8. Which of the following is the weak base electrolyte?
d) Alkyl amines
Answer: d [Reason:] NaOH, KOH and Ca(OH)2 are strong base electrolytes and the alkyl amines are the weak base electrolytes.
9. Mercuric chloride is a strong electrolyte.
Answer: b [Reason:] Almost all salts are strong electrolytes practically. The mercuric chloride and lead acetate are the weak electrolytes.
10. The degree of ionisation is given by____________
a) α = λv * λα
b) α = λv / λα
c) α = λv – λα
d) α = λv + λα
Answer: b [Reason:] The degree of ionisation is given by α = λv / λα where α = degree of ionisation, λα = equivalent conductance at infinite dilution.
11. In electrolyte, ionisation ___________ on dilution.
c) Becomes very small
d) Do not change
Answer: a [Reason:] In electrolyte, ionisation increases on dilution, till the whole of the electrolyte substance has ionised.
12. To detect the flow of current a head telephone ear piece is used instead of__________
Answer: b [Reason:] Instead of galvanometer, to detect the flow of current a head telephone earpiece is used to determine the equivalent conductance.
13. The electrolyte is placed in a special type of cell known as____________
a) Conductivity cell
b) Conductance cell
c) Equivalent cell
d) Conduction cell
Answer: b [Reason:] The electrolyte is placed in a special type of cell known as conductance cell. The conductance is made of highly resistant glass such as pyrex or quartz.
1. Sol-gel method is ________ approach.
a) Bottom up
b) Up bottom
c) Top down
d) Down top
Answer: a [Reason:] Sol-gel method is the bottom up approach for synthesis of nano materials. This process is mainly used to synthesize the nano materials.
2. Sol-gel method is known since ____________
Answer: c [Reason:] Sol-gel method is known since 1980s. The technic is rediscovered in early 1970s when the glasses were produced without high temperature melting processes.
3. The sol-gel is a __________ of solid particle.
c) Colloidal suspension
d) Cool down
Answer: c [Reason:] The sol-gel process is a colloidal suspension of the solid particles. It is also called as the molecular suspension of solid particles of ions in a solvent.
4. The gel is a ___________ mass.
a) Heavy molecular
b) Semi regid
d) Light molecular
Answer: b [Reason:] The gel is a semi regid mass. It is formed when the solvent when the solvent form sol begins to evaporate and particles or ions left behind being to join together in a continuous network.
5. Sol-gel method is ________ chemical process.
c) Semi liquid
d) Semi solid
Answer: b [Reason:] Sol-gel method is the wet chemical process. It uses a sol to produce an integrated network that is called as formation of gel.
6. __________ undergo hydrolysis and poly condensation reactions.
a) Metal ions
b) Metal carbonates
c) Metal nitrates
d) Metal oxides
Answer: d [Reason:] Metal oxides or metal chlorides undergo hydrolysis and poly condensation reactions to form a collide which is a system composed of nano particles dispersed in a solvent.
7. The solvent evolves towards the formation of an inorganic continuous network containing a ___________
a) Gaseous phase
c) Solid phase
d) Semi solid phase
Answer: b [Reason:] The solvent evolves towards the formation of an inorganic continuous network containing a gel. It also may be in liquid phase.
8. Formation of an inorganic continuous network containing the metal centres with _________
Answer: b [Reason:] Formation of an inorganic continuous network containing the metal centres with Oxo(M-O-M) or else it can be hydroxo(M-OH-M).
9. After drying process the liquid phase is removed from the gel and ___________ is performed.
Answer: a [Reason:] After drying process the liquid phase is removed from the gel and calcination is performed in order to enhance the mechanical properties. Alcohol is used as a solvent.
10. One of the advantages of sol-gel method is able to get uniform and _________ powder.
a) Micro size
b) Large size
c) Nano size
d) Small size
Answer: d [Reason:] One of the advantages of sol-gel method is able to get uniform and small size powder. Another advantage of sol-gel method is to get new micro structure and composition at low temperature.
11. Sol-gel method can produce __________ systems.
a) Uniform multi component
b) Non uniform multi component
c) Multi component
d) Non uniform multi component
Answer: a [Reason:] Sol-gel method can produce uniform multi component systems. Better control over the reactions is one of the advantages of sol-gel method.
12. Metal nano particles particularly _____________ nano particles are prepared by the chemical reduction method.
Answer: a [Reason:] Metal nano particles particularly silver nano particles are prepared by the chemical reduction method. This method is also belongs to bottom up approach.
13. The ___________ and citrate solution are used as reducing agents in chemical reduction method.
a) Hydrazine hydrate
d) Semi carbazene
Answer: a [Reason:] The hydrazine hydrate and citrate solution are used as reducing agents in chemical reduction method. The hydrazine hydrate is of 2-12ppm and citrate solution of 1ppm is used.
14. To remove the excess silver ions the solution is washed with _________ under nitrogen stream.
a) Heavy water
b) Mineral water
c) Deioniser water
d) Impure water
Answer: c [Reason:] To remove the excess silver ions the solution is washed with deioniser water under nitrogen stream. This process must be done three times.
15. The transparent colourless solution solution is changed into pale yellow from ___________ in chemical reduction method.
a) pale blue
c) Pale red
d) Dark brown
Answer: c [Reason:] The transparent colourless solution solution is changed into pale yellow from pale red in chemical reduction method. Later the dried powder of nano powder of nano silver is obtained by freeze drying.
1. At what standard conditions does the heat of combustion calculated?
a) 26°C, 1 atm
b) 25°C, 0.5 atm
c) 25°C,1 atm
d) 26°C, 0.5 atm
Answer: c [Reason:] The standard heat of combustion Δh°c is the specific enthalpy change associated with this reaction at standard conditions, usually 25°C and 1 atm pressure. The standard heat of reaction is the difference between the heats of combustion of reactants and products.
2. Hydrogen peroxide decomposes according to the following thermochemical reaction:
H2O2 (l) → H2O (l) + 1/2 O2(g); ΔH = -98.2 kJ
Calculate the change in enthalpy, ΔH, when 1.00 g of hydrogen peroxide decomposes.
a) -2.89 kJ
b) -2.80 kJ
c) -2.00 kJ
d) -2.85 kJ
Answer: a [Reason:] Molecular mass of H2
is 34.0 (2 x 1 for hydrogen + 2 x 16 for oxygen), which means that 1 mol H2
= 34.0 g H2
Using these values:
ΔH = 1.00 g H2O2 x 1 mol H2O2 / 34.0 g H2O2 x -98.2 kJ / 1 mol H2O2 ΔH = -2.89 kJ.
3. Calculate ΔH if a piece of metal with a specific heat of 0.98 kJ-kg-1-K-1 and a mass of 2kg is heated from 22°C to 28°C.
a) 11.66 kg
b) 11.56 kg
c) 11.76 kg
d) 11.26 kg
Answer: c [Reason:] ΔH = q = cpsp× m× (ΔT) = (0.98)× (2) × (+6°) = 11.76 kg.
4. If a calorimeter’s ΔH is +2001 Joules, how much heat did the substance inside the cup lose?
a) +2000 J
b) – 2001 J
c) – 2000J
d) + 2001 J
Answer: b [Reason:] Since the heat gained by the calorimeter is equal to the heat lost by the system, then the substance inside must have lost the negative of +2001 J, which is – 2001 J.
5. Calculate the ΔH of the following reaction: CO2 (g) + H2O (g) -> H2CO3 (g) if the standard values of ΔHf are as follows: CO2 (g): -393.509 KJ/mol, H2O (g): – 241.83 KJ/mol, and H2CO3 (g): – 275.2 KJ/mol.
a) +360.139 KJ
b) +350.129 KJ
c) – 360.139 KJ
d) -350.129 KJ
Answer: a [Reason:] ΔH° = ƩΔvpΔH°f (products) – ƩΔvrΔH°f (reactants) so this means that you add up the sum of the ΔH’s of the products and subtract away the ΔH of the products:
(- 275.2 KJ) – ( -393.509 KJ + – 241.83KJ) = ( -275.2 ) – (-635.339) = + 360.139 KJ.
6. Calculate ΔH if a piece of aluminum with a specific heat of 0.9 kJ-kg-1-K-1 and a mass of 1.6 kg is heated from 286°K to 299°K.
a) 16.52 kJ
b) 17.72 kJ
c) 18.72 kJ
d) 15.52 kJ
Answer: c [Reason:] ΔH = q = cpsp× m × (ΔT) = (0.9) × (1.6) × (13) = 18.72 kJ.
7. Calculate the ΔH value of the reaction:
HCl + NH3 → NH4Cl
(ΔH values for HCl is -92.30; NH2 is -80.29; NH4Cl is -314.4).
Answer: a [Reason:] ΔH = ΔHproducts – ΔHreactants
ΔHproducts = -314.4
ΔHreactants = -92.30 + (-80.29) = -172.59
ΔH = -314.4 – 172.59 = 141.8.
8. Calculate ΔH for the reaction:
N2 + 3H2 → 2NH3
(The bond dissociation energy for N-N is 163 kJ/mol; H-H is 436 kJ/mol; N-H is 391 kJ/mol).
Answer: d [Reason:] ΔH = ΔHproducts – ΔHreactants
To use the bond dissociation energies, we must determine how many bonds
are in the products and the reactants. In NH3 there are 3 N-H bonds so in 2 NH3
there are 6 N-H bonds. In N2 there is 1 N-N bond and in 3H2 there are 3 H-H bonds.
ΔHproducts = 6(391) = 2346
ΔHreactants = 163 + 3(436) = 1471
ΔH = 2346 – 1471 = 875.
9. Consider the reaction:
N₂ + O₂ → 2NO; ΔH = +180.6 kJ
what is the enthalpy change for the formation of one mole of nitrogen (II) oxide?
a) 96.80 kJ
b) 95.30 kJ
c) 96.50 kJ
d) 95.50 kJ
Answer: b [Reason:] Here we use the conversion factor 180.6 kJ/2 mol NO.
ΔH = 1 mol NO × (180.6 kJ/2 mol NO) = 95.30 kJ.
10. Refer to Q9 and answer what is the enthalpy change for the reaction of 100.0 g of nitrogen with excess oxygen?
a) 1164 kJ
b) 1190 kJ
c) 1194 kJ
d) 1160 kJ
Answer: a [Reason:] Here, we need to convert grams of N₂ to moles of N₂ and use the conversion factor 180.6 kJ/1 mol N₂.
180.6 kJ × (1 mol N₂/28.01 g N₂) × (180.6 kJ/1 mol N₂) = 1164 kJ.
11. Calculate the work done in the following reaction when 1 mol of SO2 is oxidised at constant pressure at 50 °C. State whether work is on the system or by the system.
2SO2(g) + O2(g) → 2 SO3(g)
Given: Temperature = T = 5o °C = 50 + 273 = 323 K , R = 8.314 J K-1 mol-1 ,
a) 1435 kJ
b) 1343 kJ
c) 1345 kJ
d) 1433 kJ
Answer: b [Reason:] The reaction is 2SO2
(g) + O2
(g) → 2 SO3
Given 1 mole of SO2 is used, hence dividing equation by 2 to get 1 mol of SO2
SO2(g) + ½O2(g) → SO3(g)
Δn = nproduct (g) – nreactant (g) = (1 ) -(1 + ½) = 1 – 3/2 = – ½
Work done in chemical reaction is given by
∴ W = – Δn RT = – (-½) mol × 8.314 J K-1 mol-1 × 323 K = 1343 J
∴ W = + 1343 J
Positive sign indicates that work is done by the surroundings on the system
Work done by the surroundings on the system in the reaction is 1343 J.
12. Calculate the work done in the following reaction when 2 mol of NH4NO3 decomposes at constant pressure at 10o °C. State whether work is on the system or by the system.
NH4NO3(s) → N2O(g) + 2 H2O(g)
Given: Temperature = T = 100 °C = 100 + 273 = 373 K , R = 8.314 J K-1 mol-1
a) – 18.61 kJ
b) – 18.86 kJ
c) – 18.65 kJ
d) – 18.85 kJ
Answer: a [Reason:] The reaction is NH4
(s) → N2
O(g) + 2 H2
Given 2 mol of NH4NO3 decomposes , hence multiplying equation by 2
2 NH4NO3(s) → 2 NO(g) + 4 H2O(g)
Δn = nproduct (g) – nreactant (g) = (2 + 4) -(0) =6
Work done in chemical reaction is given by
∴ W = – Δn RT = – (6) mol × 8.314 J K-1 mol-1 × 373 K = – 18607 J
∴ W = – 18.61 kJ
Negative sign indicates that work is done by the system on the surroundings
Work done by the surroundings on the system in the reaction is – 18.61 kJ.
1. In 1928, Alexander Fleming was working on which type of Bacteria also named as “Golden Staph”?
a) Streptococcus pneumonia
b) Staphylococcal pneumonia
c) Staphylococcus aureus
d) Streptococcus aureus
Answer: c [Reason:] Alexander Fleming was trying to isolate the bacterial strains of Staphylococcus aureus , as to make an antibacterial /antibiotic against it because its infection are severe and is the most antibiotic-resistant strain.
2. Which biochemist along with Howard Florey and Ernst Chain, designed a lab-scale process to produce enough Penicillin for animal tests?
a) Sir Edward Penley Abraham
b) Dr. Norman George Heatley
c) Sir Alexander Fleming
d) Dr. Rudolph Emmerich
Answer: b [Reason:] Dr. Norman George Heatley was able to develop the technique for efficiently purifying Penicillin in bulk for animal tests and by this he invented the technique back-extraction.
3. Which type of fermentation was used by Engineers to produce penicillin on large scale during World War 2?
a) Semi-Solid Fermentation
b) Deep-Tank Fermentation
c) Biphasic Fermentation
d) Solid-State Fermentation
Answer: b [Reason:] The Deep-Tank Batch Fermentation in which there is the application of submerged culture technique which was able to produce Penicillin of Approximately 50mg/ml which grew on large scale during World War 2.
4. Is Penicillium notatum and Penicillium chrysogenum both are same in terms of yield?
Answer: b [Reason:] Penicillium chrysogenum and Penicillium notatum both yields Penicillin but P.notatum also yields Notatin, P.notatum which was first discovered by Fleming but did not produced large amounts of penicillin in contrast to P.chrysogenum.
5. Penicillin production occurs in which growth phase?
a) Lag phase
b) Log phase
c) Stationary phase
d) Death phase
Answer: c [Reason:] Like all antibiotics, Penicillin is a secondary metabolite, so is only produced in the stationary phase as Bacteria produce secondary metabolite such as Antibiotics after the active stage (log phase) of the growth cycle.
6. What is Slurry which is used in Penicillin production process?
a) Semi – Liquid mixture
b) Solid – Liquid mixture
c) Gas – Liquid mixture
Answer: a [Reason:] The Semi – Liquid mixture also known as “Undigested Slurry “which goes under the fermentation/anaerobic process and later on comes out as byproduct of fermentation process as “Digested Slurry”.
7. Which sort of Fermenter is used for production of Penicillin?
a) Batch Fermenter, Fed-Batch Process
b) Fed-Batch Fermenter, Fed-Batch Process
c) Continuous Batch Fermenter , Fed-Batch Process
d) Fed-Batch Fermenter, Batch process
Answer: a [Reason:] For Large production of Penicillin a Batch Fermenter, and a Fed-Batch Process is normally used to prolong the stationary period and so as to increase the production of Penicillin and Batch is used over continuous fermenter for large scale production and fed-batch process is used to overcome its disadvantages.
8. Which type of process is involved to produce Crystalline Potassium Penicillin?
Answer: d [Reason:] Potassium ions are added to precipitate salt of Penicillin, so as to get its pure form in the later stage and the process involved in this is salting out technique which also results in less loss of Penicillin during fermentation process.
9. Why is Procaine used in the process of production of Penicillin?
a) Because Procaine is antibiotic in nature
b) Because Procaine is antifungal in nature
c) Because Procaine is analgesic in nature
d) Because Procaine is anti-allergic in nature
Answer: c [Reason:] Procaine is an analgesic in nature as it is primarily used to reduce pain of intramuscular injection of Penicillin and which is also the derivative of cocaine probably provides the longevity to Penicillin.
10. Rotary drum tank reactor comes under which type of bioreactors?
a) Mechanically agitated bioreactors
b) Air driven bioreactors/Pneumatically agitated bioreactors
c) Non-agitated bioreactors
d) Wave bioreactors
Answer: a [Reason:] Rotary drum tank reactor comes under Mechanically agitated bioreactors because it contains Stirrer paddle which provides efficient mixing and also causes production on large scale.
11. What is the role of Surge tank in Penicillin production process?
Answer: a [Reason:] Surge tanks also known as a Recycle tank which recycles facility so that water could be circulated through the system during cleaning and sterilization of the plant and helps to overcome the disturbances in unit start-up time or batch-batch variation which commonly arises in batch operation.
12. Which of the following comes under the Downstream Process?
a) Inoculum preparation
b) Equipment sterilization
c) Media Formulation
Answer: d [Reason:] Separation is the first step in product recovery in downstream processing as it involves the separation of desired cells from the culture medium and which is mechanically done by Rotary Drum Filter.
13. Why Penicillin does not affect the human body when taken?
a) Because it is a Broad spectrum antibiotic
b) Because it is a Narrow spectrum antibiotic
c) Because it is an analgesic
d) Because it is a Narcotic drug
Answer: b [Reason:] Penicillin is the Narrow spectrum antibiotic which only kills the specific bacteria or microorganisms and not the normal bacteria or microorganisms present in Human body, in this way human body is unaffected.