Photon A: λA=400 nm
EA=λAhc=400×10−96.626×10−34×3×108=4.97×10−19 J
Photon B: νB=1016 s⁻¹
EB=hνB=6.626×10−34×1016=6.626×10−18 J
Photon C: νˉC=104 cm⁻¹ = 106 m⁻¹
λC=10−6 m
EC=λChc=10−66.626×10−34×3×108=1.988×10−19 J
Order: EB>EA>EC
The wavelength of photon ' A ' is 400 nm. The frequency of photon ' B ' is 1016 s−1. The wave number of photon ' C′ is 104 cm−1. The correct order of energy of these photons is :
Held on 28 Jan 2026 · Verified 6 Jul 2026.
C>B>A
B>A>C
A>B>C
A>C>B
Sign in to track your attempts and accuracy.
Sign in to keep a private note on this question. Nothing you write is ever public.
The ratio of mass percentage (w/w) of C : H in a hydrocarbon is $12 : 1$. It has two carbon atoms. The weight (in g) of $CO_2(g)$ formed when $3.38$ g of this hydrocarbon is completely burnt in oxygen is : (Given : Molar mass in g mol$^{-1}$ C : 12, H : 1, O : 16)
The correct order of total number of atoms present in<br>(A) $2$ moles of cyclohexane<br>(B) $684$ g of sucrose<br>(C) $90.8$ L of dihydrogen at STP<br>is:
An oxide of iron contains $69.9\%$ iron, its empirical formula, is: (Given: Molar mass of Fe and O are $56$ and $16$ g mol$^{-1}$ respectively.)
What volume of hydrogen gas at STP would be liberated by action of $50\text{ mL}$ of $H_2SO_4$ of $50\%$ purity (density $= 1.3\text{ g mL}^{-1}$) on $20\text{ g}$ of zinc ?<br>Given : Molar mass of H, O, S, Zn are $1, 16, 32, 65\text{ g mol}^{-1}$ respectively.
For the given reaction:<br>$\mathrm{CaCO}_{3}+2 \mathrm{HCl} \longrightarrow \mathrm{CaCl}_{2}+\mathrm{H}_{2} \mathrm{O}+\mathrm{CO}_{2}$<br>If $90 \mathrm{~g} \mathrm{CaCO}_{3}$ is added to 300 mL of HCl which contains $38.55 \% \mathrm{HCl}$ by mass and has density $1.13 \mathrm{~g} \mathrm{~mL}^{-1}$, then which of the following option is correct ?<br>Given molar mass of $\mathrm{H}, \mathrm{Cl}, \mathrm{Ca}$ and O are 1, 35.5, 40 and $16 \mathrm{~g} \mathrm{~mol}^{-1}$ respectively.
Work through every JEE Main Physical Chemistry PYQ, year by year.