Structure of Atom

It talks about the atom. According to the Greek philosophers earlier, the atoms were the smallest part of matter that cannot be further divisible. Later, Dalton's atomic theory suggested that atom is the ultimate particle of matter. This theory was challenged later on by experiments done towards the end of the 19th and beginning of the 20th century. These experiments found that atoms are made up of electrons, protons and neutrons.

JJ Thomson, through the cathode ray tube experiment, discovered electrons. He passes the electricity from the tube and sees rays coming from the negative end. These are tiny negatively charged particles, he named them electrons.

JJ Thomson's model of the atom proposed that an atom is like a sphere (pudding) and electrons are spread around it like a plum or chocolate chips. Basically atom is overall neutral.

The structure of an atom reflects how the atom is made, which includes the nucleus at the centre where protons and neutrons are present, and electrons revolving around the nucleus.

Uncertainty in speed = 90   $*\frac{5}{100}=4.5m/s=\Delta V$

  $\Delta x=\frac{h}{4\pi m\Delta V}=\frac{6.63*10^{-34}}{4*3.14*10^{-2}*4.5}=1.173*10^{-33}$            

For 2S, number of radial moles = $n-\mathcal{l}-1=2-0-1=1$ and ${\Psi }^2\left(r\right)$  will always be positive

$\therefore option\left(B\right)iscorrect?$ it has one radial node and it is positive.

Radius of Bohr's orbit $R_n=0.529\stackrel{o}{A}*\frac{n^2}{z}$  

Radius of Bohr's orbit for hydrogen,   $R_n=0.529\stackrel{o}{A}*n^2$

For third orbit (R₃) = $0.529\stackrel{o}{A}*9$ = r₃ and

Fourth orbit (R₄) = $0.59\stackrel{o}{A}*16=r_4$

$\therefore r_4=\frac{16r_3}{9}$  

Work function, ${?}_0=6.63*10^{-19}J$  

Threshold wavelength  ${\lambda }_0=?$  

Using ;                 ${?}_0=\frac{hc}{{\lambda }_0}$  

${\lambda }_0=\frac{hc}{{?}_0}$  

=300 * 10^-9 m = 300 nm

V =  $\frac{nRT}{P}=\frac{0.90*0.0821*300}{18*32}*760=29.21\cong 29$

For 2S, number of radial moles = $n-\mathcal{l}-1=2-0-1=1$ and ${\Psi }^2\left(r\right)$  will always be positive

$\therefore option\left(B\right)iscorrect?$ it has one radial node and it is positive.