The Structure Of The Atom And The Nucleus - CCEA - BBC Bitesize

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  2. Test
  1. Structure of the atom
  2. The structure of the nucleus
  3. Question - how many protons?
  4. Questions - the Rutherford-Bohr model

Questions - the Rutherford-Bohr model

Question

Describe in detail the present model of the atom known as the Rutherford-Bohr model.

Name the particles that make up the atom, their mass and their location.

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Relative charge Relative massLocation
Proton+11Inside the nucleus
Neutron 0 1Inside the nucleus
Electron -1 \(\frac{\text{1}}{\text{1840}}\)Orbiting the nucleus
Proton
Relative charge+1
Relative mass1
LocationInside the nucleus
Neutron
Relative charge 0
Relative mass1
LocationInside the nucleus
Electron
Relative charge -1
Relative mass\(\frac{\text{1}}{\text{1840}}\)
LocationOrbiting the nucleus

Question

The element of potassium has the symbol K.

The nucleus of an atom of potassium contains 19 protons and 20 neutrons.

Using this information complete the symbol below:

\(_{?}^{?}\textrm{K}\)

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There are 19 protons and so atomic number Z = 19.

There are 19 protons and 20 neutrons and so the mass number A = 19 + 20 = 39.

\(_{19}^{39}\textrm{K}\)

Question

The element sodium has the symbol \(_{11}^{23}\textrm{Na}\).

How many protons, neutrons and electrons can be found in the nucleus of a sodium atom?

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There atomic number Z = 11 and so there are 11 protons.

The mass number A = 23.

The number of neutrons N = A - Z = 23 - 11 = 12 neutrons.

There are no electrons in the nucleus of a sodium atom.

There are 11 protons, 12 neutrons and 0 electrons inside a sodium nucleus.

Next upTest your understandingPrevious pageQuestion - how many protons?

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