Free MCQs & Online Quiz Practice for Exams

Q: A ring contains 1.2 g of diamond. The number of carbon atoms in the ring are: (Entry test 2016)

A) Nₐ/10

B) Nₐ

C) Nₐ/2

D) 1.2Nₐ

Q: The largest number of molecules are present in: (Entry test 2017)

A) 22 g of CO₂

B) 64 g of O₂

C) 14 g of N₂

D) 90 g of H₂SO₄

Q: The number of gram atoms in 3 g of hydrogen atoms is equal to the number of gram atoms in 48 g of: (Entry test 2018)

A) N

B) C

C) O

D) O₂

Q: Which compound with the given information has greater mass in kg? (Entry test 2018)

A) 22.4 dm³ N₂ at STP

B) 2 mol of CO

C) 6.02×10²³ molecules of C₂H₄

D) All have equal mass

Q: Phosphorus exists in nature as a tetra-atomic molecule. The number of atoms present in 1 gram molecule of phosphorus are: (Entry test 2018)

A) 2.41×10²⁴

B) 6.02×10²³

C) 1.20×10²⁴

D) 4.82×10²⁴

Q: The volume of CO₂ produced by heating 33.5 g of Li₂CO₃ at room temperature and pressure (M = 67 g/mol) is: (Entry test 2018)

A) 1.0×10³

B) 3×10⁷

C) 3×10¹

D) 0.33×10¹

Q: 2KClO₃ → 2KCl + 3O₂ For the production of 33.6 dm³ of O₂ at STP, the mass of KClO₃ to be decomposed is (M = 122.5 g/mol): (Entry test 2018)

A) 245.0 g

B) 61.25g

C) 122.5 g

D) 367.5

Q: Which one of the following series is observed in the visible region of electromagnetic radiation? (Entry test 2005)

A) Pfund series

B) Balmer series

C) Lyman series

D) Brackett series

Q: The constancy of e/m ratio for an electron shows that: (Entry test 2006)

A) Electron mass is 1/837th of proton

B) Electrons are universal particles of all matter

C) Electrons are produced in discharge tube only

D) None of the above

Q: Transition from n = 4, 5, 6 … to n = 3 in hydrogen spectrum gives: (Entry test 2007)

A) Pfund series

B) Lyman series

C) Paschen series

D) Brackett series

Q: For H atom which one of the following statements is correct? (Entry test 2008)

A) The radius of the orbits are integral multiple of Bohr radius

B) The angular momentum is n·h/2π

C) The energy in the nth orbit is n times the ground state energy

D) None of the above

Q: In the discharge tube emission, the cathode rays require: (Entry test 2008)

A) Low potential and low pressure

B) Low potential and high pressure

C) High potential and high pressure

D) High potential and low pressure

Q: Particles involved in an ordinary chemical reaction are: (Entry test 2009)

A) Protons

B) Neutrons

C) Electrons

D) All of the above

Q: A ball of mass 1 gram is moving with a velocity of 10⁶ m/s. The de Broglie wavelength of the ball is: (Entry test 2009)

A) 1.326×10⁻³⁶ m

B) 3.315×10⁻³³ m

C) 4.97×10²⁶ m

D) 3.15×10³ m

Q: An orbital may never be occupied by: (Entry test 2009)

A) 1 electron

B) 2 electrons

C) 3 electrons

D) 0 electron

Q: Nitrogen has three unpaired electrons according to: (Entry test 2010)

A) Hund’s rule

B) Aufbau rule

C) Pauli’s exclusion principle

D) Thumb rule

Q: The charge of an electron was determined by observing the effect of electric field on the rate of fall of oil droplets under gravity. This was done by: (Entry test 2010)

A) J.J. Thomson

B) E. Rutherford

C) R.A. Millikan

D) W.C. Roentgen

Q: Who postulated the following equation for energy emission when an electron drops from state n₂ to n₁? (Entry test 2010)

A) Einstein

B) Bohr

C) Rutherford

D) Heisenberg

Q: The energy of an electron in the excited state n = 4 in hydrogen atom is: (Entry test 2010)

A) −13.6 eV

B) −3.4 eV

C) −0.85 eV

D) −1.5 eV

Q: The number of orbitals in M shell of an atom is: (Entry test 2011)

A) 1

B) 4

C) 5

D) 9