You need to know the mass number to work it out. I can see you have it but it's not visible on your photo.

Every proton weighs 1 and every neutron weighs 1 so if you know the total mass of the nucleus and the number of protons, then you can do:
Mass Number - Proton Number = Neutron Number
because the rest of the mass (that isn't from the protons) must come from the neutrons. Make sense?

3 0

3 years ago

Suppose electrons in a TV tube are accelerated through a potential difference of 2.00 104 V from the heated cathode (negative el

Ivanshal [37]

Answer:

83816746.4254 m/s

Explanation:

m = Mass of electron = $9.11\times 10^{-31}\ kg$

q = Charge of electron = $1.6\times 10^{-19}\ C$

V = Voltage = $2\times 10^4\ V$

The kinetic energy of the electron is

$K=\dfrac{1}{2}mv^2$

Energy is given by

$E=qV$

Balancing the energy

$qV=\dfrac{1}{2}mv^2\\\Rightarrow v=\sqrt{\dfrac{2qV}{m}}\\\Rightarrow v=\sqrt{\dfrac{2\times 1.6\times 10^{-19}\times 2\times 10^4}{9.11\times 10^{-31}}}\\\Rightarrow v=83816746.4254\ m/s$

The velocity of the electrons is 83816746.4254 m/s

5 0

3 years ago

Which particle is not part of an atom?

Vladimir [108]

The particle that is not a part of the atom is the magnetic domain

4 0

4 years ago

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