# Multiple choice question for engineering

## Set 1

1. Mechanical energy satisfy which of the following?

a) Completely Convertible

b) Non-convertible

c) Partially convertible

d) None of the mentioned

### View Answer

2. Which of the following is not an example of mechanical energy?

a) Kinetic energy

b) Potential energy

c) Internal energy

d) Work

### View Answer

3. Which of the following allows complete conversion of mechanical energy?

a) Frictionless process

b) Dissipative process

c) Mixing of components

d) All of the mentioned

### View Answer

4. Which process allows complete conversion of mechanical energy?

a) Irreversible

b) Reversible

c) None of the mentioned

d) Both of the mentioned

### View Answer

5. The mechanical energy balance is the product of equation of motion and which of the following?

a) Mass

b) Velocity

c) Volume

d) None of the mentioned

### View Answer

6. Bernoulli equation is valid for which process?

a) Reversible

b) Irreversible

c) None of them

d) Both of them

### View Answer

7. What is the height difference of the water (density = 1000 Kg/m^{3}), if the change in velocity is 2 m/s and change in pressure is 100 Pa?

a) 0.21 m

b) 0.42 m

c) 0.56 m

d) 0.84 m

### View Answer

^{2}/2)/10 = 0.21 m.

8. What is the height difference of the water (density = 1000 Kg/m^{3}), if the change in velocity is 10 m/s and change in pressure is 500 Pa?

a) 1.01 m

b) 5.05 m

c) 10.1 m

d) 20.2 m

### View Answer

9. What is the height difference of the water (density = 1000 Kg/m3), if the change in velocity is 10 m/s and change in pressure is 1000 Pa?

a) 1.4 m

b) 2.9 m

c) 4.2 m

d) 5.1 m

### View Answer

^{2}/2)/10 = 5.05 m.

10. What is the height difference of the water (density = 1000 Kg/m^{3}), if the change in velocity is 6 m/s and change in pressure is 2000 Pa?

a) 1.2

b) 2.0

c) 3.6

d) 4.4

### View Answer

^{2}/2)/10 = 2.0 m.

11. What is the reversible work done if 5 m^{3} of an ideal gas is compressed isothermally from 1 Pa to 5 Pa?

a) 4.41 J

b) 8.01 J

c) 10.20 J

d) 14.18 J

### View Answer

_{2}= 1*5/5 = 1 m

^{3}, => W = –

_{5}∫

^{1}pdv = –

_{5}∫

^{1}(5/v) dv = 5 ln5 = 8.04 J.

12. What is the reversible work done if 4 m^{3} of an ideal gas is compressed isothermally from 2 Pa to 8 Pa?

a) 2.01 J

b) 6.11 J

c) 8.56 J

d) 11.09 J

### View Answer

_{2}= 2*4/8 = 1 m

^{3}, => W = –

_{4}∫

^{1}pdv = –

_{4}∫

^{1}(8/v) dv = 8 ln4 = 11.09 J.

13. What is the reversible work done if 8 m^{3} of an ideal gas is compressed isothermally from 4 Pa to 16 Pa?

a) 12.48 J

b) 28.55 J

c) 44.36 J

d) 56.96 J

### View Answer

_{2}= 8*4/16 = 2 m

^{3}, => W = –

_{8}∫

^{2}pdv = –

_{8}∫

^{2}(32/v) dv = 32 ln4 = 44.36 J.

14. What is the reversible work done if 4 m^{3} of an ideal gas is compressed adiabatically pV1.5 = K from 2 Pa to 16 Pa?

a) 4 J

b) 16 J

c) 24 J

d) 56 J

### View Answer

_{2}= (2*4

^{1.5}/16)

^{1/1.5}= 1 m

^{3}, => W = –

_{4}∫

^{1}pdv = –

_{4}∫

^{1}(16/v

^{1.5}) dv = 16 J.

15. What is the reversible work done if 4 m^{3} of an ideal gas is compressed adiabatically pV2.5 = K from 1 Pa to 32 Pa?

a) 18.6 J

b) 20.4 J

c) 24.6 J

d) 26.2 J

### View Answer

_{2}= (1*4

^{2.5}/32)

^{1/2.5}= 1 m

^{3}, => W = –

_{4}∫

^{1}pdv = –

_{4}∫

^{1}(32/v

^{2.5}) dv = 18.6 J.

## Set 2

1. What is the pressure of a gas at T = 227^{o}C, it is given that A = 5, B = 4 X 104 and C = 0 if T is in kelvin and p in mm Hg?

a) 0.024 mm Hg

b) 0.049 mm Hg

c) 0.075 mm Hg

d) 0.096 mm Hg

### View Answer

^{3}/(273 +227) = -3, => p = 0.049 mm Hg.

2. A material’s mass is given by the equation, m = 32P^{0.02}/T^{0.5}, where T is in Kelvin, m is in Kg and P is in mm Hg, what is the mass of material at 127^{o}C, use A = 10, B = 6 X 10^{3} and C = 0?

a) 1.44 Kg

b) 1.69 Kg

c) 1.96 Kg

d) 2.25 Kg

### View Answer

^{3}/(400) = -5, => p = 0.0067 mm Hg, => m = 32*(0.0067)

^{0.02}/400

^{0.5}= 1.44 Kg.

3. If the pressure of a gas at 27^{o}C is 15 mm Hg, what will be its pressure at 127^{o}C, use B = 5 X 10^{3}, C = 0, T is in kelvin and P is in mm Hg?

a) 579 mm Hg

b) 775 mm Hg

c) 961 mm Hg

d) 999 mm Hg

### View Answer

_{1}/P

_{2}= B (1/T

_{2}– 1/T

_{1}), => ln 15/P

_{2}= 5 X 10

^{3}(1/400 – 1/300), P

_{2}= 961 mm Hg.

4. Pressure of a gas at 127^{o}C is 10 mm Hg and the pressure at 527^{o}C is 20 Pa, what is the value of B?

a) 225.1

b) 365.5

c) 499.2

d) 554.5

### View Answer

5. Pressure of a gas at temperature T is P, What is the pressure of the gas at 2T, use B = 1?

a) Pe^{1/T}

b) Pe^{1/2T}

c) Pe^{1/3T}

d) Pe^{1/4T}

### View Answer

_{2}= 1*(1/2T – 1/T), => P

_{2}= Pe

^{1/2T}.

6. What is the pressure of CO_{2} at 325 K, if it is given that pressure at 330 K is 6 Pa, and pressure at 320 K is 4 Pa?

a) 4.5 Pa

b) 5 Pa

c) 5.5 Pa

d) 6 Pa

### View Answer

_{325K}= 4 + (325 – 320)*(6 – 4)/(330 – 320) = 4 + 5*2/10 = 5 Pa.

7. Temperature of SO_{2} at 5 Pa is 395 K and at 10 Pa temperature is 420 K, what is the temperature at 6 Pa?

a) 400 K

b) 405 K

c) 410 K

d) 415 K

### View Answer

_{6Pa}= 395 + (6 – 5)*(420 – 395)/(10 – 5) = 395 + 5 = 400 K.

8. At which of the following values of pressure a solid melts first?

a) 5 atm

b) 720 mm Hg

c) 500 KPa

d) 40 Torr

### View Answer

9. A liquid evaporates first at which of the following conditions?

a) High attraction forces

b) Low attraction forces

c) Low vapor pressure

d) High boiling point

### View Answer

10. At triple point, vapor pressure of ice is given by ln p* = 18 – 2560/T, and vapor pressure of water is given by ln p* = 28 – 5120/T, what is the temperature at triple point?

a) 225 K

b) 256 K

c) 320 K

d) 400 K

### View Answer

11. The vapor pressure of liquid benzene is given by ln p* = 15 – 1280/T, and that of vapor benzene is given by ln p* = 23 – 2560/T, what is the boiling point of benzene?

a) 160 K

b) 200 K

c) 240 K

d) 300 K

### View Answer

12. The vapor pressure of a compound in liquid phase is given by ln p* = 21 – 2800/T, and in solid phase it is given by ln p* = 28 – 3500/T, what is the sublimation temperature of the compound?

a) 100 K

b) 120 K

c) 150 K

d) 200 K

### View Answer

13. For CaOCl_{2}, the rate of evaporation is given by W = 325p^{0.5}M/T^{1.5} g/liter, where T is in K, p in mm Hg, and M is molecular weight, if its pressure is given by ln p* = 25 – 2700/T, what is the evaporation rate at T = 150 K?

a) 256 g/liter

b) 499 g/liter

c) 571 g/liter

d) 744 g/liter

### View Answer

^{0.5}*127/150

^{1.5}= 744 g/liter.

14. What is the vapor pressure of ammonia at 305 K, if it is given that the vapor pressure of ammonia at 315 K is 5 mm Hg and at 325 K it is 6 mm Hg?

a) 1 mm Hg

b) 2 mm Hg

c) 3 mm Hg

d) 4 mm Hg

### View Answer

15. The pressure of a compound at 200 K is 10 mm Hg and at 400 K it is 50 mm Hg, what is the pressure at T = 250 K?

a) 18.1 mm Hg

b) 24.2 mm Hg

c) 36.3 mm Hg

d) 48.4 mm Hg

### View Answer

## Set 3

1. What is the mole fraction of sodium with moles n in a solution with moles of solvent N?

a) N/n

b) n/N

c) n/(n + N)

d) N/(n + N)

### View Answer

2. What is the unit of mole fraction?

a) Kg/m^{3}

b) N/m^{3}

c) m^{-2}

d) None of the mentioned

### View Answer

3. If the mole fraction of 4.5 moles of solute is 0.5, what is the number of moles of solvent?

a) 9

b) 4.5

c) 1.5

d) 3

### View Answer

4. What is the mass fraction of 4 moles of Sodium in 8 moles of Hydrogen chloride?

a) 0.24

b) 0.48

c) 0.56

d) 0.72

### View Answer

5. If the mole fraction of sodium is 0.25 in 9 moles of liquid carbon dioxide, what is the mass fraction of sodium?

a) 0.10

b) 0.15

c) 0.20

d) 0.25

### View Answer

6. A solution has 25% w/w solution of Sodium Chloride in 10 grams of water what is the mole fraction of Sodium Chloride?

a) 0.05

b) 0.06

c) 0.07

d) 0.08

### View Answer

7. If the mole fraction of SO_{2} in H_{2}SO_{4} is 0.2, what is the ratio of mass of sulfur and oxygen in the solution?

a) 0.166

b) 6

c) 1.8

d) 0.555

### View Answer

_{2}and H

_{2}SO

_{4}be x and y respectively, => x/(x + y) = 0.2, => y/x = 4, => ratio of mass of sulfur and oxygen in solution = (x*32 + y*32)/ (x*2(16) + y*4(16)) = 0.555.

8. A mixture of gases SO_{2}, O_{2} and 4 g of N_{2} and total mass of mixture is 10 g, what is the sum of mole fraction of SO_{2} and O_{2}?

a) 0.25

b) 0.5

c) 0.75

d) 1

### View Answer

_{2}and O

_{2}= 1 – 4/10 = 0.75.

9. A neutral gas that is made of nitrogen and hydrogen only contains 7 g of nitrogen is in a mixture of with total mass 17 g, what is the mass fraction of the gas?

a) 0.5

b) 0.25

c) 0.45

d) 0.8

### View Answer

_{3}, => moles of nitrogen = moles of NH

_{3}= 7/14 = 0.5, => mass of hydrogen = 1.5*1 = 1.5 g => total mass of NH

_{3}= 7 + 1.5 = 8.5 g, => mass fraction = 8.5/17 = 0.5.

10. A mixture contains 23 g of ethanol and 36 g of water, some acetic acid is added to the mixture and its mole fraction becomes 0.5, how much acetic acid was added?

a) 25 g

b) 75 g

c) 100 g

d) 150 g

### View Answer

11. A mixture contains 9 gram each of H_{2}O and NaCl, what is the mole fraction of NaCl?

a) 0.15

b) 0.23

c) 0.45

d) 0.64

### View Answer

12. A mixture contains 10 grams each of CH4, H_{2}O, and SO_{2}, what is the mole fraction of CH4?

a) 0.14

b) 0.31

c) 0.46

d) 0.67

### View Answer

13. A mixture contains 80% of HCl and 20% H_{2}O by weight, what is the mole fraction of HCl?

a) 0.15

b) 0.29

c) 0.45

d) 0.66

### View Answer

14. A mixture contains 80% of NaOH and 20% H_{2}O by weight, what is the mole fraction of NaOH?

a) 0.24

b) 0.42

c) 0.64

d) 0.78

### View Answer

15. A compound contains 40% of Sulphur and 60% of Oxygen, what is the empirical formula of the compound?

a) SO2

b) SO3

c) SO4

d) None of the mentioned

### View Answer

## Set 4

1. Feed of a reactor has 0.25 mass fraction of H_{2}O and 0.75 mass fraction of CO_{2} with rate 4 g/hr, if the product rate is 20 g/hr what is the mass of CO_{2} in the product side?

a) 3 grams

b) 9 grams

c) 15 grams

d) 21 grams

### View Answer

_{2}will be same on both sides, => mass of CO

_{2}in the product side = 20*0.75 = 15 grams.

2. A reactor has feed of two streams, stream 1 has CO_{2} and H_{2}O with mass fraction of 0.4 and 0.6 and rate 10 kg/hr, and stream 2 has CO_{2} and H_{2}O with mass fraction 0.1 and 0.9 and rate 40 Kg/hr, what the mass fraction of CO_{2} in the product stream?

a) 0.08

b) 0.16

c) 0.24

d) 0.32

### View Answer

_{2}in product stream = (0.4*10 + 0.1*40)/(10 + 40) = 0.16.

3. A reactor has feed from 2 streams, one with rate 10 Kg/hr and other with 30 Kg/hr, and product side also has 2 streams one of which is at the rate of 15 Kg/hr, what is the rate of other product stream?

a) 5 Kg/hr

b) 15 Kg/hr

c) 25 Kg/hr

d) 35 Kg/hr

### View Answer

4. Feed of a reactor has 0.75 mass fraction of O_{2} and some SO_{2}, if the product rate is 1000 Kg/hr then what is the rate of SO_{2} in the feed?

a) 100 Kg/hr

b) 250 Kg/hr

c) 750 Kg/hr

d) 1000 Kg/hr

### View Answer

_{2}= (1 – 0.75)*1000 = 250 Kg/hr.

5. A reactor has two feed streams with the ratio of their rate as 1:9 and has O_{2} and O_{3} with the mass fraction of 0.6 and 0.4 in stream 1 and 0.2 and 0.8 in stream 2, what is the mass fraction of O_{2} in the product side?

a) 0.24

b) 0.48

c) 0.72

d) 0.96

### View Answer

6. A reactor with efficiency 50%, has the feed CO_{2} and SO_{2} with mass fraction 0.4 and 0.6 with the rate 10 Kg/hr, what is the rate of CO_{2} in product side?

a) 0.5 Kg/hr

b) 1 Kg/hr

c) 1.5 Kg/hr

d) 2 Kg/hr

### View Answer

_{2}= 5*0.4 = 2 Kg/hr.

7. A reactor has feed rate of 10 Kg/ hr and 5 Kg/hr and product rate of 9 Kg/hr, what is the efficiency of the reactor?

a) 10%

b) 30%

c) 60%

d) 100%

### View Answer

8. Waste water flowing with TSS concentration 40 mg/L at the rate of 10 Liter/min is discharged into the river, if the river is flowing at the rate of 15 Liter/min, what is the concentration of TSS in the river?

a) 10 mg/L

b) 30 mg/L

c) 45 mg/L

d) 60 mg/L

### View Answer

9. Water flowing with chlorine concentration 10 mg/L at the rate of 20 Liter/min, is discharged into a river, if the concentration of chlorine in river is 5 mg/L what is the flow rate of river?

a) 10 Liter/min

b) 20 Liter/min

c) 30 Liter/min

d) 40 Liter/min

### View Answer

10. Water flowing with TSS at the rate of 40 Liter/min, is discharged into a river flowing at the rate of 20 Liter/min, if the concentration of TSS in the river is 5 mg/L, what is the concentration of TSS in water?

a) 5 mg/L

b) 10 mg/L

c) 15 mg/L

d) 20 mg/L

### View Answer

11. The rate of flow in stream with 20% CH_{4} and 80% H_{2}O is 5 mole/hr, the contained was initially filled with 3 mole of H_{2}O, what will be the percentage of CH_{4} in product stream?

a) 5

b) 12.5

c) 25

d) 37.5

### View Answer

_{4}= 1/(1 + 4 + 3)*100 = 12.5%.

12. The rate of flow in stream with 20% O_{2} and 80% CO_{2} is 5 mole/hr, the contained was initially filled with 3 mole of O_{2}, what will be the percentage of O_{2} in product stream?

a) 12.5

b) 25

c) 37.5

d) 50

### View Answer

_{2}= 4/(4 + 4)*100 = 50%.

13. The rate of flow in stream with 40% O_{2} and 60% CO_{2} is 10 mole/hr, the contained was initially filled with 6 mole of O_{2}, what will be the percentage of O_{2} in product stream?

a) 12.5

b) 25

c) 50

d) 62.5

### View Answer

_{2}= 10/(10 + 6)*100 = 62.5%.

14. The rate of flow in stream with 50% O_{2} and 50% CO_{2} is 10 mole/hr, the contained was initially filled with 10 mole of O_{2}, what will be the percentage of O_{2} in product stream?

a) 25

b) 50

c) 75

d) 100

### View Answer

_{2}= 15/(10 + 10)*100 = 75%.

15. The rate of flow in stream with 75% O_{2} and 25% CO_{2} is 20 mole/hr, the contained was initially filled with 5 mole of O_{2}, what will be the percentage of O_{2} in product stream?

a) 20

b) 40

c) 60

d) 80

### View Answer

_{2}= 20/(10 + 15)*100 = 8%.

## Set 5

1. Which of the following is constant in a closed system?

a) Energy

b) Mass

c) Temperature

d) Momentum

### View Answer

2. How is the boundary wall of a closed system?

a) Impermeable

b) Permeable

c) Rigid

d) None of the mentioned

### View Answer

3. Desert Cooler is an example of which of the following?

a) Closed System

b) Open System

c) Isolated System

d) None of the mentioned

### View Answer

4. A jar filled with water is an example of which of the following?

a) Closed System

b) Open System

c) Isolated System

d) None of the mentioned

### View Answer

5. A pressure cooker is an example of which of the following?

a) Closed System

b) Open System

c) Isolated System

d) None of the mentioned

### View Answer

6. A country is an example of which of the following?

a) Closed System

b) Open System

c) Isolated System

d) None of the mentioned

### View Answer

7. An egg is an example of which of the following?

a) Closed System

b) Open System

c) Isolated System

d) None of the mentioned

### View Answer

8. The human body is an example of which of the following?

a) Closed System

b) Open System

c) Isolated System

d) None of the mentioned

### View Answer

9. What is the accumulation in the system after 10 second if the out flow and in flow rates are 10 g/s and 15 g/s?

a) 5 g

b) 10 g

c) 50 g

d) 100 g

### View Answer

10. What is the accumulation in the system after 4 second if the out flow and in flow rates are 3 g/s and 8 g/s?

a) 12 g

b) 20 g

c) 32 g

d) 40 g

### View Answer

11. The flow in rate of A is 5 mole/s, it undergoes a reaction A -> 2B, what are the moles of B that comes out after 5 seconds?

a) 5

b) 10

c) 25

d) 50

### View Answer

12. The flow in rate of A is 8 mole/s, it undergoes a reaction 3A -> B, what are the moles of B that comes out after 6 seconds?

a) 5

b) 8

c) 10

d) 16

### View Answer

13. The flow in rate of A and B are 5 mole/s and 10 mole/s respectively, which under goes reaction A + 2B -> 3C, what is the flow out rate of C?

a) 5 mole/s

b) 10 mole/s

c) 15 mole/s

d) 20 mole/s

### View Answer

14. The flow in rate of A and B are 4 mole/s and 8 mole/s respectively, which under goes reaction A + B -> 3C, what is the flow out rate of C?

a) 4 mole/s

b) 8 mole/s

c) 12 mole/s

d) 24 mole/s

### View Answer

15. The flow in rate of A and B are 8 mole/s and 10 mole/s respectively, which under goes reaction 4A + 5B -> 3C, what is the flow out rate of C?

a) 4 mole/s

b) 6 mole/s

c) 8 mole/s

d) 10 mole/s