Question

If velocity of a particle is 3 times of that of electron and ratio of de brogile wavelength of particle to that of electron is $1.814\times {10}^{-4}.$ The particle will be:-

• A. Neutron
• B. Deutron
• C. Alpha
• D. Tritium

Answer 1

Answer: (A)

Neutron

We know that,

$\frac{m_p}{m_e}=\frac{1.7\times {10}^{-27}}{9.1\times {10}^{-31}}$

$\frac{m_p}{m_e}$ for alpha particle is -

Mass of $1$ mole of $\alpha$ particle $=4g/mol$

Mass of $1\alpha$ particle $=\frac{4}{6.022\times {10}^{-23}}=6.64\times {10}^{-27}kg$

$m_p/m_e$ for alpha particles $=\frac{6.64\times {10}^{-24}}{9.1\times {10}^{-21}}=7300$

$m_p/m_e$ for deuterium particle $=3650$

$m_p/m_e$ for Tritium particle $=\frac{9.98\times {10}^{-27}}{9.1\times {10}^{-31}}=57.70$

$\therefore$ $m_p/m_e$ ratio for neutron's is closest.