Subject

Chemistry

Class

NEET Class 12

Test Series

Take Zigya Full and Sectional Test Series. Time it out for real assessment and get your results instantly.

Test Yourself

Practice and master your preparation for a specific topic or chapter. Check you scores at the end of the test.

 Multiple Choice QuestionsMultiple Choice Questions

11.

Electronk configuration of hydride ion is :

  • 1so

  • 1s1

  • 1s2

  • 1s12s1


C.

1s2

D.

1s12s1

Hydride ion = H- = 1s2


12.

Bond order in benzene is :

  • 1

  • 2

  • 1.5

  • none of these


C.

1.5

Benzene has the following resonancestructures -

Hence , is it bond order is 1.5 .


13.

Least ionised salt is :

  • KCl

  • AgCl

  • MgCl2

  • CaCl2


B.

AgCl

According to fajan's rule , AgCl is themost covalent compound among these ,hence is the least ionic .


14.

Element having maximumaffinity is :

  • F2

  • Cl2

  • Br2

  • I2


B.

Cl2

Among halogens , the order of elctronaffinity is -

Cl > F > Br > I

Unexpectedly , florine has less electronaffinity than chlorine .It is due to greaterelctron density on F (lesser size) due towhich it fends to repel the incomingelectron .


15.

Element having maximum ionizationenergy :

  • Na

  • Li

  • K

  • Rb


B.

Li

In a group , ionsation energy decreases aswe move down .Hence Li has maximumfirst ionisation energy among these .


16.

Number of unpaired electrons in O2molecule is :

  • zero

  • one

  • two

  • four


C.

two

The molecular orbital elctronic configuration of O2 is -

O2 (16e-) = σ1s2 , σ1s2 , σ2s2 , σ2s2 , σ2px2 , π2py2, π2pz2 , π2py1 , π2pz1

Hence , it has two unpaired lectrons and is paramagnetic .


17.

Radioactive isotope of hydrogen is :

  • Uranium

  • Deuterium

  • Tritium

  • None


C.

Tritium

Tritium is only redioactive isotope ofhydrogen .Its nucleus is an stable (n/pratio = 2.0) .


18.

Suitable condition for melting of ice :

  • high temp. and high pressure

  • high temp. and low pressure

  • low temp. and low pressure

  • low temp. high pressure


A.

high temp. and high pressure

The favourable conditions for melting ofice are high temperature and highpressure according to Le-chatelierprinciple .

Icewater


19.

In exothermic reaction heat is :

  • given out

  • absorbed

  • not involved

  • given out or absorbed


A.

given out

In exothermic reactions heat is alwaysgiven out by the reaction .For exothermicreactions -

ΣHR >ΣHP


20.

Number of moles of K2Cr2O7reduced byone mole of Sn2+:

  • 13

  • 3

  • 16

  • 6


A.

13

One mole of Sn2+car reduce13moles of K2Cr2O7 .