Assertion (A) : Radius of H+ is 1.5 × 10–3 pm.
Reason (R) : H+ cannot exist independently.
Assertion (A) : Radius of H+ is 1.5 × 10–3 pm.
Reason (R) : H+ cannot exist independently.
Solution and Explanation
both assertion and reason are correct, but reason is not a correct explanation of assertion
Top Questions on Hydrogen
Which of the following is/are correct with respect to the energy of atomic orbitals of a hydrogen atom?
(A) \( 1s<2s<2p<3d<4s \)
(B) \( 1s<2s = 2p<3s = 3p \)
(C) \( 1s<2s<2p<3s<3p \)
(D) \( 1s<2s<4s<3d \)
Choose the correct answer from the options given below:For hydrogen-like species, which of the following graphs provides the most appropriate representation of \( E \) vs \( Z \) plot for a constant \( n \)?
[E : Energy of the stationary state, Z : atomic number, n = principal quantum number]Consider the following data:
- Heat of formation of \( CO_2(g) \) = -393.5 kJ mol\(^{-1}\)
- Heat of formation of \( H_2O(l) \) = -286.0 kJ mol\(^{-1}\)
- Heat of combustion of benzene = -3267.0 kJ mol\(^{-1}\)
The heat of formation of benzene is ……… kJ mol\(^{-1}\) (Nearest integer).An ideal gas undergoes a cyclic transformation starting from point A and coming back to the same point by tracing the path A→B→C→D→A as shown in the three cases below.
Choose the correct option regarding \(\Delta U\):- The ratio of magnitude of potential energy and kinetic energy for \(5^{th}\) excited state of hydrogen atom is
Questions Asked in JEE Main exam
In the first configuration (1) as shown in the figure, four identical charges \( q_0 \) are kept at the corners A, B, C and D of square of side length \( a \). In the second configuration (2), the same charges are shifted to mid points C, E, H, and F of the square. If \( K = \frac{1}{4\pi \epsilon_0} \), the difference between the potential energies of configuration (2) and (1) is given by:
- JEE Main - 2025
- Electromagnetic Field (EMF)
Given below are two statements:
Statement I:
will undergo alkaline hydrolysis at a faster rate than 
Statement II:
In
intramolecular substitution takes place first by involving lone pair of electrons on nitrogen.
- JEE Main - 2025
- Organic Chemistry
The effect of temperature on the spontaneity of reactions are represented as: Which of the following is correct?
- JEE Main - 2025
- Thermodynamics and Work Done
- Let \( \vec{a} = \hat{i} + 2\hat{j} + \hat{k} \) and \( \vec{b} = 2\hat{i} + 7\hat{j} + 3\hat{k} \). Let \( L_1 : \vec{r} = (-\hat{i} + 2\hat{j} + \hat{k}) + \lambda \vec{a}, \lambda \in {R} \) and \( L_2 : \vec{r} = (\hat{j} + \hat{k}) + \mu \vec{b}, \mu \in \mathbb{R} \) be two lines. If the line \( L_3 \) passes through the point of intersection of \( L_1 \) and \( L_2 \), and is parallel to \( \vec{a} + \vec{b} \), then \( L_3 \) passes through the point:
- JEE Main - 2025
- Vectors
If all the words with or without meaning made using all the letters of the word "KANPUR" are arranged as in a dictionary, then the word at 440th position in this arrangement is:
- JEE Main - 2025
- permutations and combinations
Concepts Used:
Dihydrogen
Dihydrogen is the homonuclear diatomic molecule built from two hydrogen atoms. This molecule characterizes a covalent bond between two hydrogen atoms, satisfying each of their required pair configurations.
Structure of Dihydrogen:
The dihydrogen molecule characterizes a single covalent bond between the two hydrogen atoms that comprise it. This molecule has a linear shape and is nonionic in nature. Each hydrogen atom comes up with one electron towards the covalent bond.
Properties of Dihydrogen:
- At Standard Temperature and Pressure (STP), dihydrogen exists in the gaseous state.
- The melting point of H2 is 13.99 Kelvin. Transforming this value to the celsius scale, the melting point of dihydrogen can be expressed as -259.16 degrees celsius.
- The boiling point correlated with dihydrogen corresponds to 20.271 on the Kelvins scale. Transforming this value into the celsius scale, the boiling point of H2 can be represented as -252.879 degrees celsius.
- The latent heat of fusion associated with the H2 molecule correlates to 0.117 kilojoules per mole.
- The latent heat of vaporization (also known as the enthalpy of vaporization) of dihydrogen is equivalent to 0.904 kilojoules per mole.