Tags Class 12th

Class 12th

Get insights from 12k questions on Class 12th, answered by students, alumni, and experts. You may also ask and answer any question you like about Class 12th

Follow Ask Question

12k

Questions

Discussions

Active Users

Followers

New answer posted

a year ago

Class 12th Dual Nature of Radiation and Matter

de Broglie wavelength of proton = λ and that of an a particle is 2λ. The ratio of velocity of proton to that of a particle is:

0 Follower 2 Views

alok kumar singh

Contributor-Level 10

$? = \frac{h}{p}$

$? = \frac{h}{m v_{p}}$

and $2 ? = \frac{h}{4 m v_{?}}$

$\frac{1}{2} = \frac{4 v_{?}}{v_{p}}$

$\frac{v_{p}}{v_{?}} = 8$

0 0

New answer posted

a year ago

Class 12th Chemistry Coordination Compounds

The effective atomic number of Fe in K₄[Fe(CN)₆] is

0 Follower 1 View

alok kumar singh

Contributor-Level 10

EAN = Atomic No. – Oxidation state + 2 * CN

= 26 – 2 + 2 * 6

=36

0 0

New answer posted

a year ago

Class 12th Chemistry

Which among the following is malachite?

0 Follower 2 Views

alok kumar singh

Contributor-Level 10

0 0

New answer posted

a year ago

Class 12th Physics

Determine the lowest energy of photon emitted in Balmer series of hydrogen atom.

0 Follower 3 Views

alok kumar singh

Contributor-Level 10

For 3 ->2 transitions

DE = 13.6 $(\frac{1}{4} ? \frac{1}{9})$

= 13.6 * $\frac{5}{36}$

= 1.88 eV

0 0

New answer posted

a year ago

Class 12th Solutions

If vapour pressure of two liquids A and B in pure state are 400 and 500 mm of Hg respectively then mole fraction of A in vapour phase of solution obtained by mixing equal moles of A and B is

0 Follower 5 Views

alok kumar singh

Contributor-Level 10

0 0

New answer posted

a year ago

Class 12th Chemistry Solutions

Which of the following aqueous solution has highest boiling point?

0 Follower 2 Views

alok kumar singh

Contributor-Level 10

Higher the value of (ixM), higher will be the boiling point of solution.

Solute

Glucose

NaCl

K₂SO₄

K4 [Fe (N)₆]

van't Hoff

factor (i)

0 0

New answer posted

a year ago

Class 12th Chemistry

Packing efficiency of fcc lattice is

0 Follower 5 Views

alok kumar singh

Contributor-Level 10

For FCC lattice

Packing efficiency =

0 0

New answer posted

a year ago

Class 12th Chemistry

The first co-ordination number of Cs⁺ in CsCl lattice is

0 Follower 4 Views

alok kumar singh

Contributor-Level 10

CsCl has BCC structure in which Cl^– is present at corners of cube and Cs⁺ at body centre

0 0

New answer posted

a year ago

Class 12th Physics

The length of a potentiometer wire is ?. A cell of emf E is balanced at a length ?/4 from the positive end of the wire. If the length of the wire is increased by ?/2, at what distance will the same cell give a balanced point? (Potentiometer battery is ideal)

0 Follower 3 Views

alok kumar singh

Contributor-Level 10

0 0

New answer posted

a year ago

Class 12th Physics

The spectrum of a black body at two temperature 127°C and 527°C is shown in the figure. Let A1 and A2 be the areas under the two curves respectively. The value A_1/A_{2 is:}