Find the energy of each of the photons which (i) corresponds to light of frequency 3×1015 Hz. (ii) have a wavelength of 0.50 Å
Find the energy of each of the photons which (i) corresponds to light of frequency 3×1015 Hz. (ii) have a wavelength of 0.50 Å
Solution and Explanation
(i) Energy (E) of a photon is given by the expression, E = hv
Where, h = Planck's constant = 6.626 × 1034 Js
frequency of light = 3 × 1015Hz
Substituting the values in the given expression of E:
E = (6.626 × 1034) (3 × 1015)
E = 1.988 × 1018 J
(ii) Energy (E) of a photon having wavelength is given by the expression, E = \(\frac{hc}{\lambda}\)
h = Planck's constant = 6.626 × 1034 Js
c = velocity of light in vacuum = 3×108m/s
Substituting the values in the given expression of E:
E = \(\frac{(6.626\times 10^{-34})(3\times10^8)}{0.50\times10^{-10}}\) = 3.976 × 10-15 J
∴ E = 3.98 × 10-15 J
Top Questions on Atomic Models
- Choose the Incorrect Statement about Dalton's Atomic Theory
- JEE Main - 2024
- Chemistry
- Atomic Models
- Magnetic moment due to the motion of the electron in nth orbit of Bohr atom is proportional to nx. The value of x is
- JEE Main - 2024
- Chemistry
- Atomic Models
- Electrons in a cathode ray tube have been emitted with a velocity of \(1000\, m s ^{-1}\). The number of following statements which is/are true about the emitted radiation is _______ Given : \(h =6 \times 10^{-34} J s , m _e=9 \times 10^{-31} kg\)
(A) The deBroglie wavelength of the electron emitted is \(66667 nm\)
(B) The characteristic of electrons emitted depend upon the material of the electrodes of the cathode ray tube
(C) The cathode rays start from cathode and move towards anode
(D) The nature of the emitted electrons depends on the nature of the gas present in cathode ray tube- JEE Main - 2023
- Chemistry
- Atomic Models
Identify the correct statements about alkali metals
A. The order of standard reduction potential \(\left( M ^{+} \mid M \right)\)for alkali metal ions is \(Na > Rb > Li\)
B. \(CsI\)is highly soluble in water.
C. Lithium carbonate is highly stable to heat.
D. Potassium dissolved in concentrated liquid ammonia is blue in colour and paramagnetic.
E. All the alkali metal hydrides are ionic solids.
Choose the correct answer from the options given below:- JEE Main - 2023
- Chemistry
- Atomic Models
The number of s-electrons present in an ion with 55 protons in its unipositive state is
- JEE Main - 2023
- Chemistry
- Atomic Models
Questions Asked in CBSE Class XI exam
- Find the sum to indicated number of terms in each of the geometric progressions in 1, – a, \(a^2\), –\(a^3\), ... n terms (if a ≠ – 1).
- CBSE Class XI
- geometric progression
- Find n if n-1P3: nP3 = 1: 9.
- CBSE Class XI
- Permutations
- Give a brief description of the principles of the following techniques taking an example in each case.(a) Crystallisation (b) Distillation (c) Chromatography.
- CBSE Class XI
- Organic Chemistry- Some Basic Principles and Techniques
- Three reasons why the author’s grandmother was disturbed when he started going to the city school.
- CBSE Class XI
- The Portrait of a lady
- Draw diagrams showing the formation of a double bond and a triple bond between carbon atoms in \(C_2H_4\) and \(C_2H_2\) molecules.
- CBSE Class XI
- Bond Parameters
Concepts Used:
Structure of Atom
Atomic Structure:
The atomic structure of an element refers to the constitution of its nucleus and the arrangement of the electrons around it. Primarily, the atomic structure of matter is made up of protons, electrons and neutrons.
Dalton’s Atomic Theory
Dalton proposed that every matter is composed of atoms that are indivisible and indestructible.
The following are the postulates of his theory:
- Every matter is made up of atoms.
- Atoms are indivisible.
- Specific elements have only one type of atoms in them.
- Each atom has its own constant mass that varies from element to element.
- Atoms undergo rearrangement during a chemical reaction.
- Atoms can neither be created nor be destroyed but can be transformed from one form to another.
Cons of Dalton’s Atomic Theory
- The theory was unable to explain the existence of isotopes.
- Nothing about the structure of atom was appropriately explained.
- Later, the scientists discovered particles inside the atom that proved, the atoms are divisible.
Subatomic Particles
- Protons - are positively charged subatomic particles.
- Electron - are negatively charged subatomic particles.
- Neutrons - are electrically neutral particles and carry no charge
Atomic Structure of Isotopes
Several atomic structures of an element can exist, which differ in the total number of nucleons.These variants of elements having a different nucleon number (also known as the mass number) are called isotopes of the element. Therefore, the isotopes of an element have the same number of protons but differ in the number of neutrons. For example, there exist three known naturally occurring isotopes of hydrogen, namely, protium, deuterium, and tritium.