Top Chemistry MCQS
All Questions for: Top Chemistry MCQS
Question 201: Compounds of nitrogen and phosphorus are mostly________________?
- A all varieties are possible
- B ionic
- C polar
- D covalent
Explanation: The correct answer to the question is: covalent
Question 202: Which one of the following is not the use of graphite ?
- A Abrasive
- B Lubricant
- C Electrode of electrolytic cell
- D Lead pencils
Explanation: The correct answer to the question is: Abrasive
Question 203: Which one of the following acids is present in lemon juice ?
- A Citric acid
- B Oxalic acid
- C Benzoic acid
- D Tartaric acid
Explanation: The correct answer to the question is: Citric acid
Question 204: What is chemical symbol for Tungsten?
- A Z
- B T
- C Tn
- D W
Explanation: The correct answer to the question is: W
Question 205: Ketones are comparatively less reactive than aldehdye. It is due to_______________?
- A Both A and B
- B alkyl groups are electron donating
- C none
- D steric hindrance
Explanation: The correct answer to the question is: Both A and B
Question 206: Shiff’s reagent gives pink color with ____________?
- A Acetaldehyde
- B Acetone
- C Acetic acid
- D Methyl acetate
Explanation: The correct answer to the question is: Acetaldehyde
Question 207: Which of the following compounds is not soluble in HNO3___?
- A PbS
- B CuS
- C AgCl
- D CdS
Explanation: The correct answer to the question is: AgCl
Question 208: The number of atoms present in 21.6 gram of silver (atomic weight = 108) are same as the molecules in__________?
- A 4.6 gram of CHOH
- B 12 moles of KMnO
- C 0.6N HSO
- D 1.8 gram of HO
Explanation: The correct answer to the question is: 12 moles of KMnO
Question 209: Octane rating of Gasoline can be increased by __________?
- A Reforming
- B None of These
- C Cracking
- D Refining
Explanation: The correct answer to the question is: Reforming
Question 210: Actinides are the elements with atomic number from:
- A 101 to 115
- B 89 to 103
- C 97 to 104
- D 36 to 43
Explanation: The correct answer to the question is: 89 to 103
Question 211: Which one of the following compounds usually smells like garlic ?
- A H3PO3
- B All have same smell
- C P2O3
- D P2O5
Explanation: The correct answer to the question is: P2O3
Question 212: What is the molecular formula of Benzenetriozonide ?
- A C6H5O8
- B C6H5O9
- C C6H6O9
- D C6H6O6
Explanation: The correct answer to the question is: C6H6O9
Question 213: Addition of 2% gypsum in cement________________?
- A Triggers hydrolysis
- B all of the above
- C Prevents rapid hardening
- D Triggers hydration
Explanation: The correct answer to the question is: Prevents rapid hardening
Question 214: Neoprene is _______________?
- A synthetic rubber
- B Natural rubber
- C All of the above
- D Vulcanized rubber
Explanation: The correct answer to the question is: synthetic rubber
Question 215: SO3 is not absorbed in water directly because__________________?
- A All of above
- B Reaction is exothermic
- C It is insoluble in water
- D Dilute acid is produced
Explanation: The correct answer to the question is: Reaction is exothermic
Question 216: Sum of protons and neutrons in an atom gives off _________ ?
- A Both A and B
- B Mass number
- C Atomic number
- D Nucleon numbera
Explanation: The correct answer to the question is: Both A and B
Question 217: For the reaction 2HI ____________> H2+ I2
- A Kp= kc
- B Kc > kp
- C Kp ≤ kc
- D Kp > kc
Explanation: The correct answer to the question is: Kp= kc
Question 218: In SI base units, 1 Bq is equal to __________ ?
- A 0.01 disintegration per second
- B 1 disintegration per second
- C 10 disintegration per second
- D 1.5 disintegration per second
Explanation: The correct answer to the question is: 1 disintegration per second
Question 219: If heat is to be supplied continuously to a liquid at its boiling point, the temperature remains constant because:
- A The forces of attractions become stronger
- B The vapour pressure of the boiling liquid becomes greater than the external pressure
- C Extra heat is spread in the air
- D High energy molecules continuously leaving the surface of liquid
Explanation: The correct answer to the question is: High energy molecules continuously leaving the surface of liquid
Question 220: Which of the following noble gases is abundant in air?
- A Helium
- B Methane
- C Argon
- D Neon
Explanation: The correct answer to the question is: Argon
Question 221: Which is methyl cyanide_________________?
- A CH3NH2
- B CH3NO2
- C CH2 = CH – CN
- D CH3CN
Explanation: The correct answer to the question is: CH3CN
Question 222: Carboxylic acid on reduction with HI / phosphorous yields_________________?
- A alkane
- B alcohols
- C aldehydes
- D ketones
Explanation: The correct answer to the question is: alkane
Question 223: Cyclopentene is a _________?
- A None of These
- B Aliphatic
- C Alicyclic
- D Aromatic
Explanation: The correct answer to the question is: Alicyclic
Question 224: Atoms of all the elements always contain in nucleus:
- A Neutron
- B Proton
- C Neutron and electron
- D Proton and neutron
Explanation: The correct answer to the question is: Proton
Question 225: The hydrogenation of phenol in the presence of Ni and heat gives_________________?
- A n – hexane
- B cyclohexanol
- C cyclohexane
- D 1 – hexanol
Explanation: The correct answer to the question is: cyclohexanol
Question 226: Which of the following is known as absolute zero?
- A 273.16C°
- B -273.16C°
- C 0C°
- D 273K
Explanation: The correct answer to the question is: -273.16C°
Question 227: Nitrate (NO3) ions are obtained by the process of __________?
- A Nitrification
- B Denitrification
- C Fermentation
- D None of these
Explanation: The correct answer to the question is: Nitrification
Question 228: Coinage metals are actually_________?
- A Transition metals
- B Alkali metals
- C Halogens
- D Alkaline earth metals
Explanation: The correct answer to the question is: Transition metals
Question 229: What is the chemical symbol of “Potassium”?
- A Pt
- B K
- C Po
- D P
Explanation: The correct answer to the question is: K
Question 230: Vulcanized rubber is an example of ______________?
- A None of These
- B Natural polymers
- C semisynthetic polymers
- D Synthetic polymers
Explanation: The correct answer to the question is: semisynthetic polymers
Question 231: The second nuclear weapons used in warfare over Nagasaki, Japan, contain energy equal about of TNT?
- A 25 kilotons
- B 30 kilotons
- C 1.5 kilotons
- D 20 kilotons
Explanation: The correct answer to the question is: 20 kilotons
Question 232: Process used to separate insoluble particles from liquids is ___________ ?
- A Filtration
- B Sieving
- C Drying
- D Extraction
Explanation: The correct answer to the question is: Filtration
Question 233: Alkali and alkaline earth metals impart colours when heated over burner. It is due to______________?
- A Smaller electronegativity of alkali metals
- B Excitation of electrons from low energy levels to higher energy levels
- C De-excitation of electrons from higher energy levels to low energy level
- D Smaller ionic radius of these metals
Explanation: The correct answer to the question is: De-excitation of electrons from higher energy levels to low energy level
Question 234: Boron is non-netal whereas A1 is metal. It is due to_______________________?
- A No authorized justification yet
- B Small size
- C Both A and B
- D High nuclear charge
Explanation: The correct answer to the question is: Both A and B
Question 235: Pressure remain constant, at which temperature the volume of gas becomes twice of what it is at 0°C?
- A 273 K
- B 200°C
- C 546 K
- D 546 °C
Explanation: The correct answer to the question is: 546 K
Question 236: Oxygen and sulphur resemble in all except________________?
- A Polymeric
- B Show allotropy
- C Electronic conviguration of valence shell electrons
- D Show same oxidation state
Explanation: The correct answer to the question is: Show same oxidation state
Question 237: Grignard reagent gives carboxylic acid with____________?
- A CH3CHO
- B COC2
- C HCN
- D CO2
Explanation: The correct answer to the question is: CO2
Question 238: What is the color of precipitates of AgCl?
- A Yellow
- B White
- C Green
- D Blue
Explanation: The correct answer to the question is: White
Question 239: Phosphoric acid is a weak acid and its basicity is____________________?
- A zero
- B 2
- C 1
- D 3
Explanation: The correct answer to the question is: 3
Question 240: Viscosity of a liquid________by increasing temperature?
- A Increases
- B None
- C Decreases
- D Remains same
Explanation: The correct answer to the question is: Decreases
Question 241: Presence of nitrogen in organic compounds is tested as__________?
- A Nitrogen gas
- B CN‾
- C NO
- D NH3
Explanation: The correct answer to the question is: CN‾
Question 242: Water molecule is________?
- A Pyramidal
- B Angular
- C Triangular planer
- D V-shaped
Explanation: The correct answer to the question is: V-shaped
Question 243: Which of the following method is used to separate Hydrogen gas from water Gas?
- A Cyber Twinkling process
- B Steam process
- C Bosch Process
- D Palladium process
Explanation: The correct answer to the question is: Bosch Process
Question 244: which of the following pair is not distinguished by passing H2S?
- A Hg, Pb
- B Cd , Pb
- C Zn, Mn
- D As, CD
Explanation: The correct answer to the question is: Hg, Pb
Question 245: The petrol having octane number 80 has ____________?
- A 20% n- heptane + 80% iso-octane
- B 20% n- heptane + 80% n-octane
- C 80% n-heptane + 20% n- octane
- D 80% n- heptane + 20% iso-octane
Explanation: The correct answer to the question is: 20% n- heptane + 80% iso-octane
Question 246: Product formed when 2-pentyne reacts with ozone in the absence of Zinc is __________?
- A CHCHCHO + CHCOOH
- B CHCOOH + CO
- C CHCHCHO + CHCHO
- D CHCHCOOH + CHCOOH
Explanation: The correct answer to the question is: CHCHCOOH + CHCOOH
Question 247: Carnalite has chemical formula__________________?
- A KCI.MgCl2.6H2O
- B CaCO3.MgCO3
- C KCI
- D Na2B4O7.10H2O
Explanation: The correct answer to the question is: KCI.MgCl2.6H2O
Question 248: Allotropic form of phosphorus that is poisonous is___________________?
- A Black
- B White
- C Violet
- D Red
Explanation: The correct answer to the question is: White
Question 249: Dry distillation of calcium acetate results in the formation of_________________?
- A acetaldehyde
- B acetone
- C methane
- D formaldehyde
Explanation: The correct answer to the question is: acetone
Question 250: The quality of petrol is improved by ____________?
- A Cracking
- B Refining
- C Reforming
- D Hydration
Explanation: The correct answer to the question is: Reforming