Chemistry MCQ (Multiple Choice Questions) - SchoolingAxis

Chemistry MCQ (Multiple Choice Questions)

 Que- Diameter of an atom is in the order of: 

a. 2m 

b. 2mm 

c. 2nm 

d. 2pm 


Answer- 2nm


Que-  Which of the following are isoelectronic species? 

a. H+ H H- 

b. Li+ Na+ K+ 

c. C1- Br- I 

d. F- Ne Na+ 


Answer- F- Ne Na+


Que-  Mass spectrometer is used to determine Mass number of isotopes and 

a. Atomic number 

b. Relative abundance 

c. Electronic configuration 

d. All of the above 


Answer- Relative abundance


Que-  The number of peaks obtained in mass spectrometry shows 

a. Relative abundance 

b. Average mass of element 

c. Number of isotopes 

d. Relative isotopic mass 


Answer- Number of isotopes


Que-  Empirical formula of chloroform is 

a. CH2 C12 

b. CH3C1 

c. CC14 

d. CHC13 


Answer- CHC13


Que-  Which one is true about isotope? 

a. Same number of neutrons 

b. Same mass number 

c. Same physical properties 

d. Same chemical properties 


Answer- Same chemical properties


Que-  Molecular mass of water (18g) means 

a. 1-mole molecules of water 

b. 1-gram molecule of water 

c. 3-gram atoms 

d. all 


Answer- all


Que-  Which of the following ion formation is always exothermic? 

a. Uni-negative 

b. Uni-positive 

c. Di-negative 

d. Di-positive 


Answer- Uni-negative


Que-  Which of the following statements about isotopes is correct? 

a. Isotopes with odd atomic number are abundant 

b. Isotopes with odd atomic number and even mass number are abundant 

c. Isotopes with even atomic number and even mass number are abundant 

d. Isotopes with even atomic number and odd mass no are abundant 


Answer- Isotopes with even atomic number and even mass number are abundant


Que-  The sample of isotopes of an element which needs not to be vaporized in the vaporization chamer 

a. Gas 

b. Liquid 

c. Volatile solid 

d. All 


Answer- Gas


Que-  One mole of CO2 contains. 

a. 022 x 1023 atoms of oxygen 

b. 22-gram electrons 

c. 022 x 1023 atms of carbon 

d. both b & c 


Answer- both b & c


Que-  Avogadros number may represent 

a. volume of particles 

b. number of particles 

c. mass of particles 

d. All of the above 


Answer- All of the above


Que-  The number of isotopes of elements with even mass number and even atomic number are. 

a. 280 

b. 300 

c. 154 

d. 54 


Answer- 154


Que-  Size of molecule depends upon 

a. Atomicity 

b. Shape of molecule 

c. Both a and b 

d. Difficult to predict 


Answer- Both a and b


Que-  Which of the following terms is not used for ionic compound? 

a. formula unit 

b. empirical formula 

c. molecular formula 

d. formula mass 


Answer- molecular formula


Que- 36 moles of each aluminium and oxygen react with each other to produce aluminium oxide. The amount of product formed is 

a. 18 mole 

b. 27 mole 

c. 24 mole 

d. 09 mole 


Answer- 18 mole


Que-  Which of the following terms is used for the mass of chlorine 35.5? 

a. relative atomic mass 

b. mass number 

c. atomic weight 

d. relative isotopic mass 


Answer- relative atomic mass


Que-  Which one of the following has the maximum number of isotopes? 

a. oxygen 

b. carbon 

c. tin 

d. chlorine 


Answer- tin


Que-  Which one of the following is not the mono isotopic element? 

a. arsenic 

b. uranium 

c. iodine 

d. nickel 


Answer- uranium


Que-  The volume occupied by 2.8 g of N2 at STP 

a. 24 dm3 

b. 4 dm3 

c. 12 dm3 

d. 112 dm3 


Answer- 24 dm3


Que-  The mass of decimole of electrons (NA) is 

a. 008 mg 

b. 184 mg 

c. 054 mg 

d. 4 mg 


Answer- 054 mg


Que-  The number of moles of CO2 which contains 16 g of oxygen is 

a. 25 

b. 5 

c. 75 

d. 1 


Answer- 5


Que-  Which of the following statements is wrong about isotopes? 

a. they possess different mass number 

b. they possess different physical properties 

c. they possess same chemical properties 

d. they possess different position in the periodic table 


Answer- they possess different position in the periodic table


Que-  How many isotopes have odd atomic number? 

a. 154 

b. 280 

c. 86 

d. 300 


Answer- 86


Que-  Qualitative analysis is carried out for 

a. identification of elements 

b. estimation of amounts of elements 

c. molar ration of elements 

d. molar volume of elements 


Answer- identification of elements


Que-  Percentage of calcium in calcium carbonate is 

a. 80% 

b. 30% 

c. 40% 

d. 20% 


Answer- 40%


Que-  Combustion analysis is performed to determine 

a. Empirical formula 

b. Molecular mass 

c. Molecular formula 

d. Formula mass 


Answer- Empirical formula


Que-  Mostly elements have fractional atomic masses because of 

a. mass of an atom itself is in fraction 

b. atomic masses are average masses of isobars 

c. atmoic masses are average masses of isotopes proportional to their relative abundance 

d. atmoic masses are average masses of isotopes 


Answer- atmoic masses are average masses of isotopes proportional to their relative abundance


Que-  Isotopes differ in 

a. properties which depend upon mass 

b. arrangement of electrons in orbitals 

c. chemical properties 

d. all of the above 


Answer- properties which depend upon mass


Que-  Which of the following is not a macromolecule? 

a. sand 

b. haemoglobin 

c. diamond 

d. maltose 


Answer- maltose


Que-  Which of the following methods is used to estimate hydrogen in an organic compound? 

a. Combustion method 

b. Dumas method 

c. Kjeldahls method 

d. All of the above methods are for different purposes 


Answer- Combustion method


Que-  Isotopes of the same elements has 

a. different number of protons 

b. same number of neutrons 

c. different number of neutrons 

d. same mass number (nucleon number) 


Answer- different number of neutrons


Que-  The nucleus of an atom of every element will always contain 

a. neutrons 

b. protons and electrons 

c. protons 

d. protons and neutrons 


Answer- protons


Que-  When cationic molecular ions are allowed to pass through strong magnetic field in mass spectrometer which of the following ions is fallen 

a. lighter 

b. intermediate 

c. heavier 

d. are collected at same time 


Answer- lighter


Que-  When 0.5 mole of phosphoric acid is dissolved in aqueous solution how many moles of -ve and +ve ions are collected altogether? 

a. 5 

b. 1 

c. 5 

d. 2 


Answer- 2


Que-  For which of the following compounds the term empirical formula cannot be applied? 

a. NaCl 

b. H2O 

c. CCI4 

d. It can be applied to all mentioned above 


Answer- It can be applied to all mentioned above


Que-  Dempsters mass spectrometer has number of zones / parts 

a. 5 

b. 4 

c. 3 

d. 2 


Answer- 5


Que-  The properties of an element mosly corresponds to that isotope which has greater 

a. Mass number 

b. Atomic mass 

c. Relative abundance 

d. all of the above 


Answer- Relative abundance


Que-  1 a.m.u = 

a. 6 x 10-27 kg 

b. 6 x 10-24 kg 

c. 6 x 10-26 kg 

d. 6 x 10-28 kg 


Answer- 6 x 10-27 kg


Que-  The letters s p d and f are used to represent which quantum numbers 

a. Principal 

b. Azimuthal 

c. Magnetic 

d. Spin 


Answer- Azimuthal


Que-  The magnetic quantum number (QN) has its values determined directly by the value of 

a. Principal (QN) 

b. Azimuthal (QN) 

c. Spin (QN) 

d. Both a & b 


Answer- Azimuthal (QN)


Que-  The atomic number of an element having maximum number of unpaired electrons in p-subshell is 

a. 7 

b. 10 

c. 12 

d. 16 


Answer- 7


Que-  When an atom absorbs energy the lines in the spectrum will appear which are 

a. Brighter 

b. Darker 

c. Colourless 

d. Hard to locate 


Answer- Darker


Que-  Colour of fluorescene produced by cathode rays depends upon 

a. Temperature 

b. Pressure 

c. Volume 

d. Composition of glass 


Answer- Composition of glass


Que-  Which one is not true about cathode rays? 

a. 11x10-31 Kg 

b. Cast shadow 

c. Heat up the platinum foil 

d. Cannot ionize 


Answer- Cannot ionize


Que-  Positive rays are produced 

a. By burning of gas 

b. By cooling of the gas 

c. By the bombardment of cathode rays on gas molecules 

d. From anode like cathode rays produced from cathode 


Answer- By the bombardment of cathode rays on gas molecules


Que-  Rutherfords planet like structure was defective and unsatisfactory because 

a. Moving e- accelerate towards the nucleus 

b. Continuous spectrum 

c. behavior of electron remain unexplained 

d. all 


Answer- all


Que-  The relationship between energy of a photon of light and its frequency is given by 

a. de-Broglie duel nature of matter 

b. Bohrs model 

c. Plancks Quantum theory 

d. Rutherfords atomic model 


Answer- Plancks Quantum theory


Que-  Splitting of spectral lines when atom is subjected to magnetic field is called 

a. Zeemans effect 

b. Starks effect 

c. Photo electric effect 

d. Compton effect 


Answer- Zeemans effect


Que-  The velocity of the photon 

a. Is independent of wavelength 

b. Depends upon source 

c. Depends upon its frequency 

d. Equals to the square of amplitude 


Answer- Is independent of wavelength


Que-  Which one of the following explain the shape of orbitals 

a. Principal of quantum number 

b. Azimuthal quantum number 

c. Magnetic quantum number 

d. Spin quantum number 


Answer- Azimuthal quantum number


Que-  Atom cannot be divided into simple unitstheorized by 

a. Rutherford 

b. Dalton 

c. Bohr 

d. Schrodinger 


Answer- Dalton


Que-  Pressure in gas discharge tube was kept 

a. 10 torr 

b. 1 torr 

c. 1 torr 

d. 01 torr 


Answer- 01 torr


Que-  The number of fundamental particles in an atom of the lightest isotope carbon are 

a. 6 

b. 12 

c. 18 

d. 20 


Answer- 18


Que-  Angle of deflection was studied by 

a. Hitorff 

b. Stoney 

c. William Crookes 

d. J.Perrin 


Answer- J.Perrin


Que-  Increase in atomic number is observed during 

a. Alpha emission 

b. Beta emission 

c. Both a & b 

d. Radioactivity 


Answer- Beta emission


Que-  Positive rays give flash on 

a. AgNO3 plate 

b. AgCl plate 

c. ZnO 

d. ZnS 


Answer- ZnS


Que-  Free neutron changes into proton with the emission of 

a. Neutrino 

b. Electron 

c. Both a & b 

d. Meson 


Answer- Both a & b


Que-  The value of e/m ratio of electron is 

a. 02 x 1023 C/kg 

b. 7588 x 1020 C/kg 

c. 1095 x 10-31 C/kg 

d. 7588 x 1011 C/kg 


Answer- 7588 x 1011 C/kg


Que-  Charge of electron was measured by 

a. J.J Thomson 

b. Millikan 

c. Rutherford 

d. Perrin 


Answer- Millikan


Que-  Rutherford bombarded ______________ particles in discovery of nucleus 

a. Gamma-rays 

b. Alpha-rays 

c. Beta-rays 

d. X-rays 


Answer- Alpha-rays


Que-  Planks theory says energy is emitted 

a. In continuous manner 

b. Discontinuous manner 

c. Simultaneously 

d. In the form of heat 


Answer- Discontinuous manner


Que-  2nd orbit is _______ away from nucleus of H-atom as compared to 1st orbit is 

a. 2-times 

b. 3-times 

c. 4-times 

d. 6 times 


Answer- 4-times


Que-  The maximum number of orbitals present in a subshell that is represented by Azimuthal quantum number = 3 will be 

a. 1 

b. 3 

c. 5 

d. 7 


Answer- 7


Que-  The correct electronic configuration of Cu is 

a. [Ar]4s1 

b. [Ar]4s2 

c. [Ar]3d104s1 

d. [Ar]3d94s2 


Answer- [Ar]3d104s1


Que-  Pfund series are produced in the spectrum of hydrogen atom 

a. when electrons jump down to 2nd- orbit 

b. when electrons jump down to 3rd- orbit 

c. when electrons jump down to 4th- orbit 

d. when electrons jump down to 5th- orbit 


Answer- when electrons jump down to 5th- orbit


Que-  Atomic orbits having same evergy are called 

a. Degenerate orbitals 

b. Bonding molecular orbitals 

c. Anti bonding molecular orbitals 

d. Half filled orbitals 


Answer- Degenerate orbitals


Que-  Sommerfelds modification in Bohrs model is 

a. Orbit is cylindrical 

b. Orbit is elliptical 

c. Orbit is longitudinal 

d. Orbit is asymmetrical 


Answer- Orbit is elliptical


Que-  When electrons collide with heavy metals than ______ are produced. 

a. Beta-rays 

b. Alpha-rays 

c. X-rays 

d. Gamma-rays 


Answer- X-rays


Que-  Atom with higher atomic number produces X-rays of 

a. Shorter wavelength 

b. Larger wavelength 

c. X-ray not produced 

d. All are possible 


Answer- Shorter wavelength


Que-  Wavelength of electron was verified by 

a. Moseley 

b. Davisson and Germer 

c. Einstein 

d. Roentgen 


Answer- Davisson and Germer


Que-  Space around nucleus where finding probability of electrons is maximum is called 

a. Orbital 

b. Orbit is elliptical 

c. subshell 

d. Electron cloud 


Answer- Orbital


Que-  Quantum number which tells the energy of electron is 

a. n 

b. 1 

c. m 

d. s 


Answer- n


Que-  Electronic configuration of K is 

a. [Ar]4s2 

b. [Ar]4s1 

c. [Kr]5s1 

d. [He]2s1 


Answer- [Ar]4s1


Que-  ____________ can expel proteons from paraffins 

a. Electron 

b. Positron 

c. Neutron 

d. None of above has such capability 


Answer- Neutron


Que-  Milikan used __________ in his atomizer 

a. Milk 

b. Honey 

c. Oil 

d. Water 


Answer- Oil


Que-  Centrifugal forces are balanced in atom by 

a. Attractive forces 

b. Repulsive force 

c. Electrons 

d. Neutrons 


Answer- Attractive forces


Que-  Spectrum is produced due to 

a. Different wavelength 

b. Different colours 

c. Different intensities 

d. all have little contribution 


Answer- Different wavelength


Que-  When 6d orbital is complete the entering electron goes into 

a. 7f 

b. 7s 

c. 7p 

d. 7d 


Answer- 7p


Que-  When electron jump into orbit 1 then series obtained is 

a. Lyman 

b. Paschen 

c. Pfund 

d. Brackett 


Answer- Lyman


Que-  Neutrons moving with an energy of 1.2 MeV are called 

a. Fast neutrons 

b. Slow neutrons 

c. Moderate neutrons 

d. All are possible 


Answer- Fast neutrons


Que-  Splitting of spectral lines when atoms are subjected to strong electric filed is called 

a. Zeeman effect 

b. Stark effect 

c. Photoelectric effect 

d. Compton effect 


Answer- Stark effect


Que-  Three quantum number have been derived from equation of 

a. de-Broglie 

b. Plancks 

c. Schrodinger 

d. Heisenberg 


Answer- Schrodinger


Que-  Which of the following has strongest intermolecular forces of attraction? 

a. Hydrogen (H2) 

b. Chlorine (Cl2) 

c. lodine (I2) 

d. Methane (CH4) 


Answer- lodine (I2)


Que-  Which has strongest bonding in the solid state? 

a. Hydrogen Chloride (HCI) 

b. Chlorine (Cl2) 

c. Xenon(Xe) 

d. Sodium Chloride (NaCI) 


Answer- Sodium Chloride (NaCI)


Que-  When substance moves from a solid to a liquid state all of the following changes occur except 

a. Molecules become more disordered 

b. K.E of the molecules decreases 

c. Intermolecular forces become weaker 

d. Molecule become further separated 


Answer- K.E of the molecules decreases


Que-  When the atoms of third layer are arranged in such a way that they directly lie above the atoms of first layer then this arrangement is called 

a. ABAB (hexagonal) 

b. ABCABC (Cubic) 

c. Orthor hombic 

d. Rhombohedral 


Answer- ABAB (hexagonal)


Que-  In order to mention the boiling point of water at 110 Degree Centigrade the external pressure should be 

a. Between 760 torr and 1200 torr 

b. Between 200 torr and 760 torr 

c. 765 torr 

d. any value of pressure 


Answer- Between 760 torr and 1200 torr


Que-  Which one is false for evaporation? 

a. Surface phenomenon 

b. Continuous 

c. Exothermic 

d. Cause cooling 


Answer- Exothermic


Que-  Vapour pressure of water at 100 Degree Centrigrade is 

a. 55 mm Hg 

b. 760 mm Hg 

c. 355 mm Hg 

d. 1489 mm Hg 


Answer- 760 mm Hg


Que-  Which one of the following does not show hydrogen bonding ? 

a. Water 

b. Ethyl alcohol 

c. Phenol 

d. Diethyl ether 


Answer- Diethyl ether


Que-  Liquid crystal is discovered  by 

a. William Crooks 

b. Fredrack Reinitzer 

c. J.J Thomson 

d. Bravis 


Answer- Fredrack Reinitzer


Que-  Which one is a conductor but is not malleable? 

a. Iron 

b. Graphite 

c. Silver 

d. Platinum 


Answer- Graphite


Que-  Hydrogen bonding is involved in 

a. Solubility 

b. Cleansing action of detergents 

c. Biological molecules 

d. All 


Answer- All


Que-  Forces of attraction which may be present between all kinds of atoms and molecules are 

a. intramolecular 

b. intermolecular 

c. van der Waal 

d. Dipole-induced dipole 


Answer- van der Waal


Que-  The density of water may be 

a. Equal to that of ice 

b. Greater than that of ice 

c. Less than that of ice 

d. All are possible 


Answer- Greater than that of ice


Que-  The quantity of heat required to convert one mole of liquid into its vapours at its boiling point is called molar heat of 

a. vaporization 

b. evaporation 

c. crystallization 

d. sublimation 


Answer- vaporization


Que-  Steam causes more sever burn than the boiling water because it possesses. 

a. Latent heat of fusion 

b. Latent heat of vaporization 

c. Latent heat of sublimation 

d. All of the above 


Answer- Latent heat of vaporization


Que-  Water has maximum density at 

a. 0Degree Centigrade 

b. 2Degree Centigrade 

c. 4Degree Centigrade 

d. 100Degree Centigrade 


Answer- 4Degree Centigrade


Que-  The conversion of vapours back into their liquid state is called 

a. crystallization 

b. evaporization 

c. vaporization 

d. condensation 


Answer- condensation

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