ECAT Pre Engineering Chemistry Chapter 5 MCQ Test With Answer

The charge of an electron is determined by

• J.J. Thomson A
• Crooks B
• Perrin C
• R.A.Millikan D

Quantum number values for 2p orbitals are

• n = 2, l = 1 A
• n = 1, l = 2 B
• n = 1, l = 0 C
• n = 2, l = 0 D

E = hv is the

• Spectral equation A
• Plank's equation B
• de Broglie's equation C
• None of these D

Which of the following element's outermost orbits last electron has magnetic quantum number m=0?

• Na A
• O B
• Cl C
• N D

• Neutrons are attracted by nucleus A
• Neutrons carry out nuclear reactions B
• Neutrons carry no charge C
• Neutrons are electromagnetic radiations D

The value of charge on electron is

• 1.602 x 10^-19coulombs A
• 1.602 x 10^-18coulombs B
• 1.602 x 10^-17coulombs C
• 1.602 x 10^-16 coulombs D

The number of spherical nodes in 3p orbitals are

• One A
• Three B
• Non C
• Two D

The de-Brogile wavelength of a particle with mass 1g and velocity 100 m/s is

• 6.63 x 10^-33m A
• 6.63 x 10^-34m B
• 6.63 x 10^-35m C
• 6.65 x 10^-35m D

The number of electrons in the M shell of the element with atomic number 24 is

• 24 A
• 12 B
• 13 C
• 8 D

In Millikan method the oil droplet falls under the force of gravity but it moves upward due to

• Electric field A
• Magnetic field B
• Incident light C
• X-rays D

Energy of electron in the infinite Bohr orbit of H-atom is

• 0 KJ/mole A
• 1 KJ/mole B
• -1 KJ/mole C
• -1313.32 KJ/mole D

If the radius of first Bohr orbit be a_o, then the radius of third Bohr orbit would be

• 3 x a_o A
• 6 x a_o B
• 9 x a_o C
• 1/2 x a_o D

When the electron jumps form second third, fourth orbit to the fist orbit, the transitions are known as

• Balmer series A
• Lyman series B
• Pfund series C
• Brackett series D

The charge over mass ratio of electron is:

• 1.6 x 10^-1 C Kg^-1

  A

• 9.1 x 10^-31 C Kg^-1

  B

• 1.7588 x 10¹¹ C Kg^-1

  C

• 6.62 x 10^-34 C Kg^-1

  D

Which of the following is not a property of cathode rays

• They can produce x-rays when they strike a heavy metal anode A
• They can cause reduction reaction B
• They produce fluorescence in rare earth and minerals C
• They comprise neutral particles D

The third line of the Balmer series, in the emission spectrum of the hydrogen atom,is due to the transition from the

• Fourth Bohr orbit to the first Bohr orbit A
• Fifth Bohr orbit to the second Bohr orbit B
• Sixth Bohr orbit to the third Bohr orbit C
• Seventh Bohr orbit to the third Bohr orbit D

In the ground state, an element has 13 electrons in its M shell. The element is

• Copper A
• Chromium B
• Nickel C
• Iron D

Which quantum number is sufficient to describe the electron is hydrogen atom?

• l A
• n B
• m C
• s D

The order of distance between the various Bohr orbits is

• r₂- r₁> r₃- r₂> r₄- r₃> ...... A
• r₁> r₂> r₂- r₃> r₄-r₃> ..... B
• r₂-r₁= r₃- r₂= r₄- r₃> ..... C
• r₂- r₁> r₃- r₂< r₄- r₃< .... D

The e.m value for positive rays maximum for:

• Oxygen. A
• Nitrogen. B
• Helium. C
• Hydrogen. D

Mass of simple electron is:

• 9.1 x 10^-31 kg

  A

• 9.1 x 10^-30 kg

  B

• 1.66 x 10^-31 kg

  C

• 9.1 x 10^-31 kg

  D

A 4f orbital has

• one node A
• two node B
• three node C
• four nodes D

The value of Plank's constant 'h' is

• 6.625 x 10^-34 A
• 6.625 x 10^-34J sec B
• 6.625 x 10^-34KJ C
• 6.625 x 10^-34K Cal D

The number of de-electrons retained in Fe²⁺ (At.No. of Fe = 26) ions is

• 3 A
• 4 B
• 5 C
• 6 D

In which of the following pairs, the numbers of electrons in the outermost shell are different?

• As,Sb A
• Ge,Sn B
• In,pt C
• Se,Te D

Orbital having same energy is called:

• Hybrid orbital. A
• Valence orbital. B
• Degenerate orbital. C
• D-orbital. D

The wave length of electron as wave is 0.5 nm. What is the wave length in meter

• 5 x 10^-9 A
• 5 x 10^-12 B
• 5 x 10^-6 C
• 5 x 10^-10 D

Charge on electron was discovered by:

• Millikan. A
• Crook. B
• Neil Bohr. C
• Rutherford. D

Which is not true with respect to cathode rays?

• A stream of electrons A
• Charged particles B
• Move with speed as that of light C
• Can be deflected by magnetic fields D

Splitting of spectral lines when atoms are subjected to strong electron field is called

• Zeeman effect A
• Stark effect B
• Photoelectric effect C
• Compton effect D