A copper wire used in an electrical circuit has a diameter of 0.56 mm.
Estimate the number of copper atoms that would fit in a line across the diameter of the wire.
Use your knowledge of the typical radius of atoms in your calculation.
Explain why your answer to (a) can only be an estimate.
A copper-63 atom contains 29 protons, 34 neutrons and 29 electrons.
The mass of an electron is 11840\displaystyle \frac{1}{1840}18401 of the mass of a proton. Assume that a neutron has the same mass as a proton.
Calculate the percentage of the mass of a copper-63 atom that is due to its electrons.
Give your answer to 3 significant figures.
The radius of the nucleus of a copper atom is about 110 000\displaystyle \frac{1}{10\,000}100001 of the radius of the atom.
Use this information and your answer to (c) to describe what these data show about the structure of an atom.
51 exam-style questions on OCR GCSE Chemistry 1.2 Atomic structure, covering 1.2.1 Development of the atomic model, 1.2.2 The nuclear model and the size of atoms, and 1.2.3 Subatomic particles in atoms and ions. Each one has a worked solution and a mark scheme showing where the marks go.