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Atomic structure

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Question 19

This question is about atomic structure.

a.

Define the term mass number of an atom.

[1]
b.

Complete the table below to show the numbers of neutrons and electrons in the species shown.

SpeciesNumber of protonsNumber of neutronsNumber of electrons
206Pb^{206}\text{Pb}206Pb82
208Pb4+^{208}\text{Pb}^{4+}208Pb4+82
[2]
c.

A sample of lead contains four stable isotopes: 204Pb^{204}\text{Pb}204Pb, 206Pb^{206}\text{Pb}206Pb, 207Pb^{207}\text{Pb}207Pb, and 208Pb^{208}\text{Pb}208Pb. This sample has a relative atomic mass of 207.3. In this sample, the ratio of the abundance of isotopes 204Pb^{204}\text{Pb}204Pb, 206Pb^{206}\text{Pb}206Pb, and 207Pb^{207}\text{Pb}207Pb is 1:15:161:15:161:15:16.

Calculate the percentage abundance of 206Pb^{206}\text{Pb}206Pb in this sample.

[3]
Markscheme

Atomic structure Questions

  1. A Level
  2. /Chemistry
  3. /Atomic structure

33 exam-style questions on AQA A Level Chemistry Atomic structure, covering Fundamental particles, Mass number and isotopes, and Electron configuration. Each one has a worked solution and a mark scheme showing where the marks go.

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