JEE Mains · Chemistry · STD 11 - 2. structure of atom
If the de Brogile wavelength of the electron in \(n^{th}\) Bohr orbit in a hydrogenic atom is equal to \(1.5\,\pi a_0\) ( \(a_0\) is Bohr radius), then the value of \(n/z\) is
- A \(0.40\)
- B \(1.50\)
- C \(1.0\)
- D \(0.75\)
Answer & Solution
Correct Answer
(D) \(0.75\)
Step-by-step Solution
Detailed explanation
\(2\pi r = n\lambda \) \(\lambda = \frac{{2\pi r}}{n} = \frac{{2\pi {n^2}{a_0}}}{{n \times Z}} = 2\pi \frac{n}{Z}{a_0}\) \(\lambda = 1.5\pi {a_0}\) \(\therefore \,2\pi \frac{n}{Z}{a_0} = 1.5\pi {a_0}\) \(\therefore \frac{n}{Z} = \frac{{1.5}}{2} = 0.75\)
See the Complete Solution
Get step-by-step explanations for this and 2.5 Lakh+ more JEE, NEET & CET questions.
- Unlock all solutions
- Practice the full chapter
- Track accuracy across PYQs
4.8 rated on Google Play · 14,000+ reviews
More questions from Chemistry
- If \(m\) and \(e\) are the mass and charge of the revolving electron in the orbit of radius \(r\) for hydrogen atom, the total energy of the revolving electron will beJEE Mains 2014 Hard
- \(2-\)Methyl propyl bromide reacts with \(C _2 H _5 O ^{-}\)and gives ' \(A\) ' whereas on reaction with \(C _2 H _5 OH\) it gives ' \(B\) '. The mechanism followed in these reactions and the products 'A' and ' \(B\) ' respectively are:JEE Mains 2023 Hard
- According to Bohr's atomic theory :- \((A)\) Kinetic energy of electron is \(\propto \frac{ Z ^{2}}{ n ^{2}}\). \((B)\) The product of velocity (v) of electron and principal quantum number (n), 'vn' \(\propto Z ^{2}\). \((C)\) Frequency of revolution of electron in an orbit is \(\propto \frac{ Z ^{3}}{ n ^{3}}\). \((D)\) Coulombic force of attraction on the electron is \(\propto \frac{ Z ^{3}}{ n ^{4}}\). Choose the most appropriate answer from the options given below :JEE Mains 2021 Easy
- \(C ( s )+ O _{2}( g ) \rightarrow CO _{2}( g )+400\; kJ\) \(C ( s )+\frac{1}{2} O _{2}( g ) \rightarrow CO ( g )+100 \;kJ\) When coal of purity \(60 \%\) is allowed to burn in presence of insufficient oxygen, \(60 \%\) of carbon is converted into \('CO'\) and the remaining is converted into \('CO _{2}\)\('\). The heat generated when \(0.6 \;kg\) of coal is burnt isJEE Mains 2022 Hard
- Match List \(I\) with List \(II\) :
Choose the correct answer from the options given below :LIST - \(I\) (Compound) LIST - \(II\) (Uses) \((A)\) Iodoform \((I)\) Fire extinguisher \((B)\) Carbon tetrachloride \((II)\) Insecticide \((C)\) \(CFC\) \((III)\) Antiseptic \((D)\) \(DDT\) \((IV)\) Refrigerants JEE Mains 2024 Medium - What amount of bromine will be required to convert 2 g of phenol into 2,4,6-tribromophenol? (Given molar mass in \(\mathrm{g} \mathrm{mol}^{-1}\) of \(\mathrm{C}, \mathrm{H}, \mathrm{O}, \mathrm{Br}\) are \(12,1,16,80\) respectively )JEE Mains 2025 Medium
More PYQs from JEE Mains
- A liquid of density \(750\,kgm ^{-3}\) flows smoothly through a horizontal pipe that tapers in crosssectional area from \(A _{1}=1.2 \times 10^{-2}\,m ^{2}\) to \(A_{2}=\frac{A_{1}}{2}\). The pressure difference between the wide and narrow sections of the pipe is \(4500\,Pa\). The rate of flow of liquid is________\(\times 10^{-3}\,m ^{3} s ^{-1}\)JEE Mains 2022 Hard
- The lengths of the sides of a triangle are \(10+ x ^{2}\), \(10+ x ^{2}\) and \(20-2 x ^{2}\). If for \(x = k\), the area of the triangle is maximum, then \(3 K ^{2}\) is equal toJEE Mains 2022 Hard
- The correct set that contains all kinds (basic, acidic, amphoteric and neutral) of oxides is:JEE Mains 2026 Medium
- Let \(f ( x )= |x -2|\) and \(g ( x )= f ( f ( x )), x \in[0,4]\) Then \(\int \limits_{0}^{3}(g(x)-f(x)) d x\) is equal toJEE Mains 2020 Medium
- In the given figure the magnetic flux through the loop increases according to the relation \(\phi_{B}(t)=10 t^{2}+20 t\), where \(\phi_{B}\) is in milliwebers and \(t\) is in seconds. The magnitude of current through \({R}=2 \,\Omega\) resistor at \({t}=5\, {s}\) is \(....\,{mA}\).
JEE Mains 2021 Medium - Let A be the focus of the parabola \(y^{2}=8x.\) Let the line \(y=mx+c\) intersect the parabola at two distinct points B and C. If the centroid of the triangle ABC is \((\frac{7}{3},\frac{4}{3})\) , then \((BC)^{2}\) is equal to:JEE Mains 2026 Medium