ECAT Pre Engineering MCQ Test With Answer for Chemistry Full Book

Equal masses of methane and oxygen are mixed in an empty container at 25°CThe fraction of total pressure exerted by oxygen is :

• 1/2 A
• 8/9 B
• 1/9 C
• 16/17 D

The higher molecular weight materials which yield on hydrolysis the amino acids is called:

• Carbohydrates A
• Lipids B
• Fatty acids C
• Proteins D

Heat absorbed or released during the chemical reaction of physical process at constant pressure is equal to

• 
  A
• 
  B
• 
  C
• 
  D

Soil remediation means

• To make it suitable for cultivation of crops A
• To make it acidic B
• To make it alkeline C
• To add manure into it D

A fuel has the same knocking property as a mixture of 70 isooctane (2, 2, 4- trimethyl pentane) and 30% n-heptane by volume the octane number of the fuel is

• 100 A
• 70 B
• 50 C
• 40 D

Which of the following is used as anesthetics

• Alcohol A
• Diethylether B
• Phenol C
• Dimethyl ether D

Elevation of boiling point is measured by

• Beckmann's apparatus A
• Lands Berger's method B
• Antifreeze apparatus C
• None of these above D

Which of these reactions is shown by buranone, CH₃COCH₂CH₃

• On warming with acidified potassium dichromative (IV) the solution turns green A
• On heating with Fehling's reagent a red precipitate is formed B
• With 2,4-dinitrophenlhydrazine reagent an orange precipitate is formed C
• With hydrogen cyanide an aldehyde is formed D

N₂O₄⇌ 2NO₂

For the above reaction, which of the Following expression of K_c correct :

• Kc = [ N₂O₄]/[ NO ₂]²

  A

• Kc = [ N₂O₄]/ [NO ₂]

  B

• Kc = [ N₂O]²/[ N₂O ₄]

  C

• Kc = [ N₂O₄]/[ N O ₂]

  D

At present cement plants in Pakistan are

• ten A
• twenty two B
• four C
• twenty four D

The sum of mole percent of all the components of solution is always equal to :

• Less than 100 A
• One B
• 100 C
• 10 D

Which Amino acid can be synthesized by over body.

• Basic amino acids A
• Acidic amino acids B
• Essential amino acids C
• Non-essential amino acids D

• Adding H₂O and H⁺ions A
• Adding OH^-ions B
• Adding O²molecules C
• Adding O atoms D

Metal used in the preparation of Grignard's reagent is:

• Ca A
• Na B
• Mg C
• Zn D

Essential amino acids are those amino acids which

• Body can not synthesize A
• Body can synthesize B
• α-amino acids C
• β-amino acids D

Burning of coal and hydrocarbon in air are examples of

• Non-spontaneous reaction A
• Spontaneous reaction B
• Natural reaction C
• Both b and c D

The unit of rate of reaction is

• mole dm^-3 A
• mole Kg^-1 B
• moles dm^-3sec^-1 C
• grams dm^-3 D

Which of the following elements should be the least metallic in character

• Rb A
• ln B
• Te C
• l D

In the atmosphere, O₂is about

• 10% A
• 15% B
• 21% C
• 25% D

Generally ionization energy of atoms decreases by

• Decreases in atomic size A
• Increase in atomic size B
• Increase in nuclear charge C
• None of these D

Which of the following is explosive:

• Trinitropheonal A
• Nitropheonal B
• Nitromethane C
• Nitrobenzene D

Caroxyl group has functional in it.

• one A
• two B
• three C
• four D

Trend of boiling point of halogens from fluorine to Iodine is that it

• Decreases A
• Is negligible B
• Increases C
• Remains constant D

Contamination of Hg comes into surface water from chlor industrial wastes. Why is Hg toxic

• It attaches to sulphur of the disulphide link A
• Hg is a heavy metal B
• Hg is liquid at room temperature C
• Hg is non reactive chemically D

Domestic waste mostly constitutes

• Non-biodegradable pollution A
• Biodegradable pollution B
• Effluents C
• Air pollution D

Ammonia contains nitrogen in it

• 46% A
• 50% B
• 80% C
• 82% D

Matals usually conduct electricity because

• There are mobile electrons in the metallic structure A
• Metals are decomposed by current B
• Metals have high resistance C
• In metals the ions are free to move D

• 
  A
• 
  B
• 
  C
• 
  D

NaHCO₃is prepared by

• Down's process A
• Solvay's process B
• Nelson's process C
• None of these D

Which set of hybrid orbitals has planar triangle shape?

• sp³ A
• sp B
• sp² C
• dsp² D